Cambodia operates a two-tier medical system where public hospitals serve the general population and private clinics in Phnom Penh and Siem Reap cater to foreigners and wealthier Cambodians. The public system faces resource shortages, inconsistent supply chains for medication, and limited English-speaking staff outside major cities. Foreign nationals requiring surgery, intensive care, or treatment for serious conditions typically evacuate to Bangkok or Singapore. The distance from Phnom Penh to Bangkok's Bumrungrad International Hospital is approximately 405 kilometers by air, a route served multiple times daily. Siem Reap to Bangkok measures roughly 400 kilometers. Medical evacuation insurance covering at least 100,000 USD is standard practice for travelers to Cambodia.
The Royal Phnom Penh Hospital, a joint venture with Thai medical groups opened in 2014, provides the highest standard of care within the country. The facility employs Thai-trained physicians and stocks imported pharmaceuticals. Naga Clinic on Street 240 in Phnom Penh handles routine issues and minor injuries for the expatriate community. Angkor Hospital for Children in Siem Reap, funded by Japanese NGO Friends Without A Border since 1999, treats pediatric cases exclusively. Adults seeking care in Siem Reap use the Royal Angkor International Hospital on National Road 6. Kampot, Battambang, and Sihanoukville have provincial hospitals staffed by Cambodian-trained physicians, but diagnostic equipment is limited and supplies inconsistent.
Dengue fever is endemic throughout Cambodia with case numbers peaking during the monsoon months from May through October. The Ministry of Health reported 18,622 dengue cases in 2022, a figure that represents reported cases only. The Aedes aegypti mosquito transmits the virus and bites primarily during daylight hours. No vaccine is available for travelers. Malaria exists in forested border areas of Mondulkiri, Ratanakiri, Preah Vihear, and Oddar Meanchey provinces. Phnom Penh, Siem Reap, Battambang, and the Tonle Sap Lake area are considered low risk for malaria. The dominant strain in Cambodia is Plasmodium falciparum, which shows resistance to chloroquine. Atovaquone-proguanil, doxycycline, or mefloquine are recommended for travelers visiting high-risk areas. The Cambodian National Malaria Center documented declining case numbers from 46,351 in 2010 to 7,504 in 2020.
Japanese encephalitis occurs in rural areas where rice farming and pig rearing coincide. The disease is transmitted by Culex mosquitoes that breed in flooded rice paddies and bite primarily between dusk and dawn. Two vaccine formulations exist: Ixiaro, a two-dose series given on days 0 and 28, and JE-Vax, discontinued in most markets. The vaccine is recommended for travelers spending more than one month in rural areas or visiting during the transmission season from May through October. The Cambodian Ministry of Health conducts annual vaccination campaigns targeting children under 15 in endemic provinces.
Hepatitis A and typhoid fever are foodborne and waterborne illnesses present throughout Cambodia. Hepatitis A vaccine provides protection after a single dose, with full immunity developing within four weeks. Typhoid vaccine is available as an injectable polysaccharide version or oral live attenuated capsules. The oral version requires four capsules taken on alternate days. Neither vaccine provides absolute protection, requiring continued attention to food and water safety. Hepatitis B is endemic, with an estimated prevalence of 6.1 percent in the adult population according to a 2017 study published in the BMC Infectious Diseases journal. The vaccine series consists of three injections at 0, 1, and 6 months.
Rabies exists in Cambodia's dog population with approximately 800 reported cases annually, though actual numbers likely exceed this due to underreporting. The Pasteur Institute in Phnom Penh manufactures rabies vaccine and immunoglobulin. Provincial hospitals stock vaccine inconsistently. Post-exposure prophylaxis requires four vaccine doses on days 0, 3, 7, and 14, plus immunoglobulin injection around the wound site if the individual was not previously vaccinated. Pre-exposure vaccination consists of three doses given on days 0, 7, and 21 or 28, eliminating the need for immunoglobulin and reducing post-exposure doses to two. Monkeys at Angkor Wat and Phnom Kulen are habituated to humans and bite when tourists carry visible food.
Tetanus vaccination status matters in Cambodia where soil contamination is widespread and minor injuries common. The adult vaccine schedule calls for a booster every ten years. Diphtheria is combined with tetanus in the Td vaccine recommended for adults. Pertussis can be added as Tdap, a formulation recommended once for adults who have not previously received it. The Cambodian Ministry of Health conducts school-based tetanus toxoid campaigns, but adult coverage remains below 50 percent.
Measles outbreaks occur periodically in Cambodia despite vaccination efforts. The Ministry of Health reported 1,476 measles cases in 2019. The MMR vaccine covering measles, mumps, and rubella requires two lifetime doses for full protection. Many adults born before 1970 lack documented vaccination and have not acquired natural immunity. A blood test can confirm immunity, or a single MMR dose provides protection regardless of previous status.
Air pollution in Phnom Penh deteriorates during the dry season from November through April when agricultural burning in neighboring countries combines with urban emissions. The United States Embassy in Phnom Penh operates an air quality monitor reporting real-time PM2.5 concentrations. Daily averages exceed 100 micrograms per cubic meter during peak burning season, a level the World Health Organization classifies as unhealthy. Individuals with asthma or chronic obstructive pulmonary disease should carry prescribed inhalers and consider N95 masks during high pollution days.
Tap water in Cambodia is not potable. Municipal systems exist in Phnom Penh and Siem Reap, but distribution pipes leak and storage tanks lack consistent chlorination. Bottled water is available in sealed containers at markets and convenience stores throughout the country. The local brand Pure Life is bottled by Nestlé under license at a facility outside Phnom Penh. Ice served in tourist restaurants in Phnom Penh and Siem Reap generally comes from commercial producers using filtered water, but ice in rural areas or street stalls may come from untreated sources. Boiling water for one minute at sea level kills pathogens. Chemical treatment requires either iodine tablets held for 30 minutes or chlorine dioxide tablets held for four hours.
Food safety standards vary dramatically between establishments. Restaurants catering to foreigners in Phnom Penh and Siem Reap generally observe basic hygiene practices. Street food presents higher risk due to inconsistent refrigeration and food held at unsafe temperatures. Prahok, the fermented fish paste central to Khmer cuisine, undergoes a fermentation process that creates an acidic environment inhibiting most pathogens, but contamination can occur during preparation. Fruit peeled immediately before consumption is safe. Salads washed in untreated water or prepared hours before service present risk.
Travelers' diarrhea affects an estimated 30 to 50 percent of visitors to Cambodia. The condition results from bacterial, viral, or parasitic contamination of food or water. Most cases resolve within three to five days without treatment. Loperamide slows intestinal motility and reduces symptoms but should not be used if fever or bloody stool is present. Oral rehydration solution replaces electrolytes lost through diarrhea. Packets of WHO-formulation oral rehydration salts are sold at pharmacies throughout Cambodia under various brand names. Azithromycin 500 mg as a single dose treats bacterial diarrhea, but resistance is increasing. Ciprofloxacin resistance exceeds 50 percent in some Southeast Asian studies.
Pharmacies in Cambodia operate with minimal oversight. Prescription medications including antibiotics, antimalarials, and sedatives are sold without prescription. Counterfeit pharmaceuticals enter the supply chain through porous borders with Thailand and Vietnam. The United States Pharmacopeia conducted testing in Cambodia in 2015, finding that 14 percent of antimalarial medications contained incorrect active ingredients and 9 percent contained no active ingredient. Travelers requiring chronic medications should carry sufficient supply from their home country in original packaging with accompanying documentation.