United States – Health Risks, Inoculations, Vaccinations, and Health Certificates

What are the main health risks for expats living in the United States?

The United States lacks the kind of tropical disease burden common in many developing destinations, yet it presents its own distinct combination of infectious, environmental, and lifestyle-related health challenges that newcomers should acquaint themselves with before arrival. The country’s enormous geographical footprint means that health risks differ dramatically from one region to the next, and your specific destination within the US will largely determine the hazards most relevant to you.

Tick-borne diseases represent one of the most significant vector-borne threats in the country. Lyme disease — spread via deer ticks — is particularly prevalent across the northeastern and upper midwestern states, with wooded and grassy landscapes in places such as Connecticut, New York, Pennsylvania, Massachusetts, and Minnesota posing elevated risk. Hallmark symptoms include a distinctive bull’s-eye skin rash, fever, fatigue, and aching joints. This disease is far less common in southern and western states, meaning your personal exposure depends heavily on where you end up settling.

West Nile virus, transmitted through mosquito bites, circulates throughout the continental US and reaches peak activity in late summer. The overwhelming majority of those infected show no symptoms at all or suffer only a mild flu-like illness, although a small minority can face serious neurological complications. No licensed human vaccine currently exists, so personal protective measures — applying insect repellent, keeping skin covered, and removing any standing water near your home — remain the core defences.

Valley Fever (coccidioidomycosis) is a fungal respiratory illness caused by inhaling spores disturbed from dry, dusty soils, primarily in California’s San Joaquin Valley, Arizona, Nevada, New Mexico, and portions of Texas. Expats settling in these areas — particularly those who work outdoors or pursue activities that stir up soil — face meaningful risk. Symptoms closely mimic those of pneumonia and are frequently attributed to other causes, making awareness especially important.

Hantavirus is an uncommon but potentially life-threatening respiratory disease contracted through exposure to rodent droppings or nesting debris. It occurs predominantly in rural western regions, with the highest concentration of cases historically linked to the Four Corners area where Colorado, Utah, Arizona, and New Mexico converge. Maintaining cleanliness around areas where rodents may nest and preventing rodent access to homes are sensible precautions for those living in affected rural settings.

Air quality and environmental concerns have become increasingly prominent across the western United States. Seasonal wildfires in California, Oregon, and Washington generate dense smoke laden with fine particulate matter — a genuine health threat, especially for individuals with pre-existing respiratory or heart conditions. Ground-level ozone and traffic-related particulate pollution are also concerns in densely populated urban areas. The Environmental Protection Agency (EPA) operates a daily Air Quality Index (AQI) that expats — particularly those with asthma or cardiovascular disease — should consult regularly.

Extreme heat poses a rising and serious threat, especially across the southwestern states such as Arizona, Nevada, California, and New Mexico, as well as southern states including Texas and Florida. During summer months, heatstroke and heat exhaustion are real dangers. Staying well hydrated, limiting outdoor exertion during the hottest parts of the afternoon, and ensuring access to air-conditioned spaces are all essential habits for expats in these areas.

Food and water safety is generally reliable throughout the United States, with treated municipal tap water being safe to drink in the vast majority of locations. Exceptions include some rural properties served by private wells, where bacterial or chemical contamination can occur — independent water testing is advisable if you move into a home relying on a private supply. Occasional outbreaks of foodborne illness involving pathogens such as salmonella, E. coli, and listeria do occur; the CDC and Food and Drug Administration (FDA) publish live outbreak alerts that residents can monitor.

Sexually transmitted infections (STIs) — including chlamydia, gonorrhoea, and syphilis — are tested for during the immigration medical examination. Rates of certain STIs in the US exceed those in many comparable wealthy nations, making regular sexual health screening and safe sexual practices important for all residents, not just immigration applicants.

Are any vaccinations or inoculations required before entering the United States?

It is essential to distinguish between what is required simply to cross the US border and what is mandated in the context of acquiring a green card (lawful permanent residency).

Visitors and holders of non-immigrant visas — including tourist, student, and temporary work visa holders — face no vaccination requirements as a condition of entry. No yellow fever certificate is demanded of travellers arriving from non-endemic countries, and no proof of immunisation is checked at the border for those making temporary stays.

Immigrant visa applicants and those seeking to adjust their status to permanent resident face a markedly different situation. US immigration law obligates immigrant visa applicants to receive a specified set of vaccinations prior to visa issuance. Anyone applying for an immigrant visa overseas, or seeking adjustment to lawful permanent resident status from within the United States, must be vaccinated against a range of diseases, along with any additional vaccine-preventable illnesses recommended by the Advisory Committee for Immunization Practices (ACIP).

Some of these vaccines are mandated directly by statute, while others are required because the Centers for Disease Control and Prevention (CDC) has identified them as serving the public health interest. The list of required vaccines is reviewed and updated periodically. One significant recent development: as of January 22, 2025, the COVID-19 vaccination requirement was removed from the immigration medical exam. Polio vaccine requirements were also updated in 2024: effective May 1, 2024, the Vaccination Technical Instructions for Civil Surgeons changed for the polio vaccine, and one dose of IPV should be given to anyone 2 months or older who is not currently up to date.

Applicants who have not received any of the listed vaccinations — where those vaccinations are age-appropriate and medically appropriate — are classified as having a Class A medical condition and are considered inadmissible. Waivers are available on medical, religious, or moral grounds; always seek advice from a qualified immigration attorney if this may apply to your circumstances.

Certain non-immigrant visa categories are handled differently: K (fiancé) visa applicants and refugees, for instance, are not required to be vaccinated before travelling to the US, but must meet the vaccination requirements upon applying for adjustment of status.

Which vaccinations are recommended for expats moving to the United States?

Separate from the mandatory immigration requirements, anyone relocating to the United States — regardless of visa category — should ensure their routine immunisations are fully current before departing their home country. The US vaccination schedule, maintained jointly by the CDC and ACIP, is broadly consistent with those found in other high-income nations, though certain differences deserve attention.

Routine vaccinations to be current on include:

• MMR (measles, mumps, rubella) — Two doses are expected for adults born after 1957. The MMR vaccine is only needed for people born after 1956, meaning many immigration applicants over 65 are exempt from this requirement. Given that measles outbreaks have occurred in the US in recent years, being up to date on MMR is particularly important.
• Tetanus, diphtheria, and pertussis (Tdap) — Adults who have never received a Tdap booster should do so, followed by Td booster doses at ten-year intervals.
• Polio — Polio has been eliminated in the US, and vaccination is required for immigration purposes. Adults who did not complete a childhood polio series should discuss their immunisation status with a clinician.
• Hepatitis B — This vaccine is required as part of the immigration list and is broadly recommended for all adults. Because some countries have not historically included hepatitis B in routine childhood schedules, this may represent a new requirement for certain individuals.
• Varicella (chickenpox) — Two doses are recommended for adults without clear evidence of prior immunity. Since varicella vaccination is not uniformly part of every country’s national programme, it is worth reviewing your own history carefully.
• Influenza (flu) — An annual seasonal flu vaccine is strongly encouraged for all US residents. All immigration exam applicants aged 6 months and older are required to receive the flu vaccine if their appointment falls within flu season (October through March).
• Hepatitis A — Recommended for all adults, particularly those who travel frequently or work in food-service roles.
• Meningococcal vaccine — Adolescent vaccination requirements include the addition of the hepatitis A and meningitis vaccines compared with adult requirements.
• Pneumococcal vaccines — Advised for adults aged 65 and over, as well as for certain younger adults living with underlying health conditions.
• Shingles (zoster) — Recommended for adults aged 50 and older. The shingles vaccine is widely available in the US and recommended more routinely than in some other healthcare systems worldwide.
• HPV vaccine — Recommended for individuals up to age 26 who have not previously been vaccinated, and may be appropriate for some individuals up to age 45.

One notable distinction worth highlighting: the US does not use the BCG (tuberculosis) vaccine as a routine childhood immunisation, unlike many countries across Asia, Africa, Latin America, and parts of Europe. Having received BCG as a child does not exempt you from tuberculosis screening as part of the immigration medical examination — TB testing is a standard element of that process.

It is strongly recommended that you consult a travel health specialist or general practitioner at least six to eight weeks before your departure date. Bring your complete vaccination records, including documentation from your country of origin — this may save you from unnecessarily repeating immunisations. Where records are unavailable, a titer test (a blood test measuring immunity) can be performed for certain vaccines including hepatitis A, hepatitis B, MMR, and varicella.

Do you need a health certificate to move to or work in the United States?

A formal medical examination is a legal prerequisite for those seeking to become lawful permanent residents (green card holders) in the United States. This requirement is established under the Immigration and Nationality Act and is designed to identify any health-related grounds that might render an applicant inadmissible.

Who is required to undergo the examination?

Immigrant applicants already present in the United States who are adjusting their visa status to permanent residency must receive the required vaccines unless they can produce documentation of prior vaccination, or unless a particular vaccine is medically contraindicated. Those applying for immigrant visas from abroad must complete an overseas medical examination prior to their visa interview at a US embassy or consulate.

Who conducts the examination?

If you are applying from within the United States, the examination must be carried out by a civil surgeon designated by US Citizenship and Immigration Services (USCIS). If you are applying from abroad, you must be seen by a panel physician authorised by the US Department of State. Your regular family doctor is not permitted to conduct this exam — it must be performed by an officially recognised and authorised medical professional.

Step-by-step: the immigration medical examination process

1. Find an authorised physician: Use the USCIS “Find a Doctor” tool at uscis.gov to locate a designated civil surgeon near you (for in-US applicants), or contact your local US embassy or consulate for a list of panel physicians (for overseas applicants).
2. Gather your documents: Collect your passport or government-issued ID, your complete vaccination history, and any relevant medical records. In order to avoid delays in processing, all immigrant visa applicants should have their vaccination records available for the panel physician’s review; applicants should consult their regular healthcare provider to obtain a copy of their immunisation record.
3. Attend your first appointment: At your first appointment, the doctor will review your medical and immunisation history, perform a full physical examination, order appropriate testing, recommend required immunisations, and help fill out your I-693 form. The appointment typically takes about 30–45 minutes.
4. Complete required testing: The I-693 immigration medical examination requires communicable disease screening including blood and urine tests. Tuberculosis screening using a blood test (QuantiFERON-TB Gold) is standard. Syphilis and gonorrhoea testing are also included. A chest X-ray may be required if your TB blood test is positive.
5. Receive any missing vaccinations: The civil surgeon or panel physician will determine which vaccines you require based on your age and immunisation history. USCIS only requires you to receive a single dose of each required vaccine, even if it is normally given in a series — a rule designed to avoid unnecessary delays to your application.
6. Collect your sealed results: Once all paperwork, laboratory tests, and vaccinations are finalised, the civil surgeon will provide a sealed envelope containing the completed I-693 form for USCIS. This envelope must not be opened under any circumstances.
7. Submit with your green card application: If you are applying for adjustment of status to lawful permanent resident (a green card), you must submit Form I-693 by mail together with your Form I-485. As of December 2, 2024, USCIS announced that applicants must now submit Form I-693 at the same time as their green card application (Form I-485); if you submit your green card application without the medical exam results, USCIS may reject it.

What does the examination assess?

The immigration medical examination exists to identify, for the benefit of the Department of State and USCIS, any applicants with health-related grounds of inadmissibility. It covers screening for communicable diseases of public health significance (including TB, syphilis, and gonorrhoea), assessment of any physical or mental disorders associated with harmful behaviour, and verification that all required vaccinations have been received.

How much does it cost?

An immigration medical exam costs USD $250 to $650 on average for the physical and mental evaluation, laboratory testing, and completion of the required documentation (as of 2025). However, because fees are set by individual civil surgeons rather than by the federal government, costs vary between providers. The majority of health insurance plans do not cover immigration medical examinations, which are generally classified as administrative rather than medically necessary. Always confirm the current fee directly with your chosen civil surgeon or panel physician prior to booking your appointment.

How long do results take?

The process generally involves a minimum of two visits — the first for the examination itself, records review, and testing; the second once results are available and the provider can finalise the required documentation. TB blood test results are typically returned within three to five business days. As of 2025, Form I-693 results completed on or after November 1, 2023 do not expire, though they remain tied to the specific immigration application with which they were submitted.

How does healthcare in the United States compare to what expats may be used to?

The US healthcare system is among the most distinctive — and frequently surprising — aspects of life in America for those arriving from abroad. In contrast to countries where universal, government-funded healthcare covers the entire population (such as in Canada, the UK, Australia, France, or across much of Europe), the United States operates predominantly through a private, insurance-driven model with no single-payer national health service for the general working-age population.

The public-private divide: Government-funded healthcare programmes do exist in the US, but they serve defined population groups rather than everyone. Medicare provides coverage for people aged 65 and over and those with qualifying disabilities. Medicaid is a joint federal-state programme that assists low-income individuals and families, though its eligibility rules for immigrants are strict — most legal permanent residents are required to wait five years after receiving their green card before qualifying for federal Medicaid. Newly arrived expats and those on work visas will typically need to arrange private health insurance from the very beginning of their stay.

Health insurance: The majority of working adults in the US obtain health insurance through their employer, which usually contributes a portion of the monthly premium. Those who are self-employed or whose employer does not offer coverage can purchase plans via the federal healthcare marketplace at healthcare.gov. Insurance plans differ enormously in their scope, pricing, and provider networks. Premiums, deductibles (the out-of-pocket threshold before insurance begins paying), co-pays, and co-insurance arrangements can make the overall cost structure bewildering for those accustomed to simpler systems. Taking time to read and understand your policy thoroughly is essential.

Quality and accessibility: At the upper end, American healthcare is genuinely world-class. Major metropolitan areas — including New York, Boston, San Francisco, Houston, and Chicago — host internationally respected hospitals, cutting-edge research institutions, and specialist facilities of the highest calibre. However, access to care is far from uniform across the country. Rural communities frequently face shortages of primary care doctors, and specialist hospitals may be considerable distances away. Expats considering settling outside major cities should investigate the proximity of hospital services and specialist care relevant to any existing or chronic health conditions before finalising their location.

Language: Healthcare in the United States is delivered primarily in English. In cities and regions with large Spanish-speaking communities — such as Miami, Los Angeles, parts of Texas, and the southwestern states — Spanish-speaking medical professionals are commonly available. Major urban hospitals generally provide interpreter services across a range of languages, although the consistency and quality of these services varies. In smaller towns and rural communities, language support options may be quite limited.

Practical considerations for foreign nationals: As a foreign national, you are generally able to access private healthcare in the US on the same basis as American citizens, provided you carry appropriate insurance or can pay directly. Emergency departments are legally obligated to provide stabilising treatment regardless of a patient’s insurance status or ability to pay. However, hospital charges for patients without insurance can be extraordinarily high — a single inpatient stay can generate bills running to tens of thousands of dollars. While health insurance is not typically a formal condition of visa approval or residency, it is an absolute financial necessity for virtually everyone living in the country.

What are the risks of travel within the United States, and are there regional health differences?

Stretching across a vast and climatically varied continent — from near-Arctic conditions in Alaska and the northern states to subtropical environments in Florida and Hawaii — the United States presents dramatically different health landscapes depending on where you are. Understanding regional variation is important both for everyday living and for travel within the country.

Northeast and Upper Midwest (New York, New England, Pennsylvania, Minnesota, Wisconsin): This corridor constitutes the primary Lyme disease zone in the United States. Effective tick protection — applying DEET-containing repellents, wearing long-sleeved shirts and full-length trousers, conducting thorough tick checks after time outdoors, and using tick-repellent clothing treatments — is strongly recommended from spring through to autumn. Rocky Mountain spotted fever and anaplasmosis are additional tick-borne illnesses present in these regions.

Southwest (Arizona, New Mexico, California’s Central Valley, Nevada, Utah): Valley Fever risk is concentrated in this region. Expats who spend time outdoors in dusty environments, engage in construction, gardening, or agricultural activities, or who have compromised immune systems should exercise particular caution. Extreme summer heat is a serious hazard in Arizona and Nevada, where cities such as Phoenix and Las Vegas routinely record temperatures exceeding 40°C (104°F). Altitude sickness is also worth considering for those living at elevation — Denver, Colorado sits at 1,609 metres (5,280 feet), and the surrounding Rocky Mountain region reaches considerably higher. Arriving at altitude and allowing time for acclimatisation before undertaking strenuous activities is advisable.

Southeast (Florida, Louisiana, Gulf Coast states): The region’s warm, humid climate sustains year-round mosquito populations, heightening the risk of West Nile virus transmission and, increasingly, locally acquired dengue fever in parts of southern Florida. Hurricane season (June through November) brings flooding that can generate waterborne disease risks. Florida and coastal Gulf states also experience intense UV radiation levels — wearing sunscreen and protective clothing is sensible throughout the year.

Pacific Northwest (Washington, Oregon) and California: Wildfire smoke has become a predictable seasonal health hazard, typically at its worst between July and October. Those with asthma, chronic obstructive pulmonary disease (COPD), heart disease, or other respiratory conditions should keep a close eye on air quality forecasts and be prepared to stay indoors or use N95 respirators during smoke events. The EPA’s AirNow platform (airnow.gov) offers real-time air quality data covering locations across the entire country.

Alaska and Hawaii: Alaska’s key health concerns revolve around cold weather and wilderness hazards — hypothermia, frostbite, and limited access to medical care in remote areas rank among the primary risks, along with the danger of encounters with large wildlife including bears and moose in backcountry settings. Hawaii, despite its tropical climate, is generally free of many diseases found on the US mainland, but dengue fever and leptospirosis — a bacterial infection acquired through contact with fresh water, particularly during or following flooding — are present on some islands.

Wherever your base in the US, domestic travel is generally uncomplicated. However, frequently moving between regions with very different climates, altitudes, and disease environments warrants some health planning. The CDC maintains domestic traveller health pages offering state-by-state health information to help with this.

Where can expats get reliable and up-to-date health advice for the United States?

Health requirements, vaccination mandates, and immigration medical policies are subject to change. It is essential to verify any specific requirements against current official sources rather than relying on third-party summaries. The following resources are authoritative and maintained on a regular basis:

• US Department of Health and Human Services (HHS): The federal department with overall responsibility for the nation’s public health. hhs.gov
• Centers for Disease Control and Prevention (CDC): The principal US public health authority, publishing vaccination schedules, disease outbreak notifications, and health guidance for immigrants and refugees. cdc.gov
• CDC Immigrant and Refugee Health: Targeted guidance covering medical examinations, civil surgeon information, and vaccination requirements connected to immigration. cdc.gov/immigrant-refugee-health
• US Citizenship and Immigration Services (USCIS): The official authority for immigration medical exam requirements and Form I-693, including a tool for locating designated civil surgeons. uscis.gov
• US Department of State — Vaccinations: Vaccination requirements for consular immigrant visa applicants and a directory of authorised overseas panel physicians. travel.state.gov
• World Health Organization (WHO) — United States country profile: International health context and disease surveillance data for the US. who.int/countries/usa
• Travel Health Pro (NaTHNaC, UK): A comprehensive country information page for the United States offering vaccination recommendations and destination-specific health guidance useful to travellers from any country of origin. travelhealthpro.org.uk
• EPA AirNow: Real-time air quality monitoring data by location across the US — particularly valuable for anyone with respiratory or cardiovascular conditions. airnow.gov

Always consult a qualified travel health specialist or general practitioner before relocating. Requirements, fees, and recommendations change over time — information that is accurate at the time of reading may not reflect the situation six or twelve months from now.

Frequently Asked Questions

Do I need to redo my home-country vaccinations when applying for a US green card?

Not necessarily. In order to avoid delays in processing, all immigrant visa applicants should have their vaccination records available for the panel physician’s review at the time of the immigrant medical examination; applicants should consult their regular healthcare provider to obtain a copy of their immunisation record. Provided your records are valid and confirm that required vaccines were received, you will not be asked to repeat them. For certain immunisations — including hepatitis A, hepatitis B, MMR, and varicella — a titer test (a blood test measuring existing immunity) can substitute for documentary proof if vaccination records cannot be located. Any records submitted must be in English or accompanied by a certified translation.

Is health insurance required to live or work in the United States?

Health insurance is not a formal statutory requirement for most visa categories or residency statuses in the US. Nevertheless, it is financially indispensable. Without coverage, even a brief hospitalisation can produce bills amounting to tens of thousands of dollars. Most employers provide access to group health insurance schemes, and individuals without employer-sponsored coverage can purchase plans through the federal marketplace at healthcare.gov. International health insurance is also an option, particularly during the early stages of a relocation before domestic coverage is in place.

What happens if I develop a serious illness in the United States?

In a medical emergency, dial 911 to summon ambulance services. Under the federal EMTALA law, hospital emergency departments are legally obligated to provide stabilising care regardless of a patient’s insurance status or financial circumstances. Non-emergency care without insurance, however, can come at enormous cost. For ongoing or serious illness, you will need to identify a primary care physician (commonly referred to as a PCP) who falls within your insurance network. Your insurer’s website or member services helpline is the right starting point for locating in-network providers, obtaining specialist referrals, and understanding what your plan covers.

How do I find a doctor who speaks my language in the United States?

Large hospitals and health systems in cities with diverse populations frequently offer interpreter services and may employ multilingual staff. Many health insurer websites allow you to search for providers by language spoken. Spanish-language healthcare is broadly accessible across many parts of the US. For other languages, telehealth interpretation services are increasingly being integrated into primary care practices. The Health Resources and Services Administration (HRSA) maintains a searchable directory of federally qualified community health centres — which are required by law to provide language access services — available at findahealthcenter.hrsa.gov.

Is the COVID-19 vaccine still required for my immigration medical exam?

No. With effect from January 22, 2025, the COVID-19 vaccine is no longer a requirement for completing immigration medical paperwork. This represents a significant departure from previous policy. It remains important to verify the current list of required vaccines directly with your designated civil surgeon or panel physician before your appointment, as requirements can be revised at short notice in response to updated ACIP recommendations.

How long does the immigration medical examination process take?

The process generally requires a minimum of two visits — the first for the examination, records review, and laboratory testing; the second once test results have been returned and the facility can complete all required documentation. TB blood test results typically come back within three to five business days. From first appointment to receiving your sealed I-693 envelope, you should generally allow at least one to two weeks, and potentially longer if vaccinations requiring spacing over time are identified. Build adequate time into your green card application timeline to avoid complications.

Can I use my existing international health insurance in the United States?

Many international health insurance policies do extend coverage to medical treatment received in the United States, though the US is frequently classified as one of the most costly countries for international health insurance due to the high baseline cost of American healthcare. Review your existing policy carefully to confirm whether the US is covered, and scrutinise any coverage caps, exclusions, or network restrictions that may apply. Some international policies impose limits on US-based treatment or exclude the US altogether. Once you have established permanent or long-term residency, transitioning to a US-based insurance plan may prove more appropriate and financially practical.

Are there any vaccinations unique to the United States that I may not have had before?

Most immunisations required or recommended in the US form part of standard schedules in many countries, but several differences merit attention. The meningococcal vaccine — particularly MenACWY and MenB — may be administered more routinely to adolescents and young adults in the US than in certain other health systems. The varicella (chickenpox) vaccine is absent from some countries’ national programmes, so if you have neither had chickenpox nor received the vaccine, your civil surgeon or doctor may recommend vaccination. Additionally, the shingles vaccine (Shingrix) is routinely recommended for all adults aged 50 and over in the US — a practice not universal in other healthcare systems. Discussing your full vaccination history with your healthcare provider is the best way to pinpoint any gaps.