With adventure vacations on the rise, international travelers need to make sure they have the proper vaccines before going backpacking in India or a safari in Africa.

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Vaccines to protect you from things like Hepatitis A or typhoid won’t break the bank. But there are a couple of must-have inoculations that can cost you more than $500.

While some of the more pricey vaccines may not be required to enter a country, doctors specializing in travel vaccines say they are necessary to protect you and to prevent your trip from turning into a nightmare.

“The most expensive one is a rabies shot,’’ said Dr. Brian Terry of Healthy Traveler Clinic in Pasadena, Calif. “It’s currently $600 or more for the three shot rabies series.”

One may not think a rabies shot is needed, but Terry said there are countries where rabid dogs are commonplace. Countries with high incidents of rabies include India, China, Latin America and South East Asia. Rabies attacks the central nervous system and can be deadly if untreated.

According to the Center for Disease Control, tens of thousands of people in Africa, Asia and Latin America die each year from rabid dog bites. The CDC recommends getting the vaccination under these conditions: if your travels will bring you into contact with wild or domestic animals; you will be visiting remote areas where medical care isn’t easily obtained; or if your visit is for more than one month in an area where dog rabies is common. 

Vaccination specialists Dr. Alexander Lupenko of Passport Health NY, Roslyn Heights, N.Y., said in China there are 1 million unregistered dogs.

“If you’re planning to work outside in a country for prolonged exposure you would like to be protected from rabies,” said Lupenko. 

What’s more, much of the world doesn’t offer robust medical care for dog bites, making preventive rabies shots that much more important.

“The only option in many places if you get a dog bite is to get out quickly, which could be expensive and ruin your business travel,’’ added Terry of Healthy Traveler Clinic.

The rabies vaccination is the priciest largely because there are only two manufacturers making the shots and because it’s difficult to produce, said the doctors.

Another costly vaccination is for Japanese encephalitis. A three shot series costs around $450. Japanese encephalitis is a mosquito borne disease that can cause paralysis, seizures, coma and death.

While it’s typically found in rural areas across South East Asia, this strand of encephalitis is carried by mosquitoes, which are found in cities. So it may be worth it to get the vaccine even if you’re not visiting a rural area. According to the CDC, there are 30,000 to 50,000 cases reported in Asia each year. The CDC does not recommend the Japanese encephalitis vaccine for all travelers to Asia, but suggested it for people spending a month or longer in endemic areas during the transmission season, especially if travel to rural areas are on the itinerary.

According to the CDC, countries that had major epidemics in the past but have controlled it largely via vaccination include China, Korea, Japan, Taiwan and Thailand. Other countries that have periodic epidemics include Vietnam, Cambodia, Myanmar, India, Nepal and Malaysia.

“People who would be outside at dusk and dawn would be susceptible,’’ said Lupenko of Passport Health.

Although $600 for rabies shots and $450 for shots for Japanese encephalitis may seem like a lot, the doctors said the rabies vaccination lasts a lifetime and the Japanese encephalitis vacations lasts around three years.

“You can think about amortizing the price if you’re traveling for the next ten years,’’ noted Lupenko.