Immunization Program Targets Cambodia’s Worst Preventable Diseases
tat tai village, Koh Kong province – Village Chief Svay Sim walked up and down the valley for six hours, well into the night, telling residents scattered throughout the forest to meet the next day for immunizations.
Tat Tai is in one of the most remote regions of Cambodia, a village of a few dozen low-lying huts hacked out of the forests of the Cardamom mountains. There are no health facilities for at least 60 km, and the meager livings the villagers can eke out leave them malnourished and highly exposed to malaria.
It was a perfect place to start phase one of the Expanded Program for Immunization, a full-scale assault on measles by the government, the World Health Organization and other agencies. Using the same head-on approach that eradicated polio in Cambodia, a medical field team began their campaign here last month, high in forests that were nearly impenetrable only two years ago.
For a weary Svay Sim, the team was a welcome sight, and worth the hours of night hiking.
“I talked to everyone,” he said later. “Before, we were concerned [about illnesses]. Now we are happy because the children get vaccinated.”
On the morning after his trek, all 210 of his wards trickled in by family groups of twos to half a dozen at a time, many of them carrying brightly colored umbrellas to protect them from an early morning shower that rolled down the steep peaks surrounding the village, some four hours by boat and truck from Koh Kong town.
The children, dark-skinned and bare-footed, came wearing all manner of protective charms: amulet necklaces, bells and coins.
They crowded into the village’s only pagoda, a stilted wooden building where they’d find perhaps the only real magic that would protect against illness—vaccines, syringes and tablets.
“Measles is the most serious vaccine-preventable disease in Cambodia,” said Keith Feldon, head of the immunization program, headquartered at the WHO’s Phnom Penh office. By contrast, “measles in the US is almost considered a benign disease.”
Prevalent across Cambodia, the disease kills an estimated 300 to 400 people each year. It left another 14,000 recorded victims in its wake last year alone, though WHO suspects at least three times that number went unreported. The lucky ones suffer rashes and swollen red eyes. When measles attacks the body and the supply of vitamin A is inadequate, the eyes become an almost inevitable casualty. Night blindness is common in undernourished victims. Cornea scars can lead to full blindness in one or both of the eyes.
“Sometimes the whole eye can fall out…within 24 hours,” Feldon said.
Spreading as quickly as a common cold, measles kills by destroying the body’s nutrients. Victims whither to nearly nothing and then die.
The expanded program intends to prevent all that.
Health workers intend to first attack measles in Cambodia’s most politically or geographically remote areas—former Khmer Rouge zones or in the isolated hill tribe villages scattered throughout Ratanakkiri. These are the same areas where malaria is most prevalent. Forests are a perfect habitat for malaria-carrying mosquitoes, and many people don’t have proper bed nets.
So the immunization program provides a rare opportunity for WHO’s malaria control workers to combine forces. While immunization teams will give shots and vitamin supplements, the malaria teams will diagnose villagers, dispense medicine and distribute mosquito nets.
A 2-year-old logging road made the trip to Tat Tai easier than the team had expected. Until recently, the area was entirely uninhabited. Under the Khmer Rouge regime in the 1970s, the villagers of Tat Tai were driven away from their homes and forced to settle elsewhere. Since the construction of the logging road, the families have returned and begun to reclaim the forest that had engulfed the village.
Small banana orchards are springing up, along with patches of sugar cane, plots of tobacco, small gardens and rice fields. New wooden huts pepper the valley where more families have moved in. To earn money, the families sell their bananas and fell trees the logging company left behind.
But deep inside this hilly, jungle-choked region, malnutrition and malaria are rife, and the field teams had their work cut out for them.
Almost immediately, the work began. Villagers were numbered by marker as they arrived. With assembly-line precision, the malaria and measles teams took care of them.
For malaria, villagers were tested with a new field kit that can detect p falciparum malaria, the most common strain, which also causes death in about 15 minutes. Those with a fever were considered to have malaria too, and moved along the line, with new markings on their hands: “F” for fever and a “+” for malaria. The F’s and pluses were given the anti-malaria drug Mefloquin.
Preap Poa, a 22-year-old mother of two daughters was marked with a plus.
“I don’t know what causes the fever,” she said. “Maybe by mosquitoes or water. It’s because the sanitation here is not good.”
To get any kind of medicine, though, Preap Poa and her fellow villagers usually have to travel to larger towns closer to the coast. With the good road, they can usually make that trip in a day “if someone has a vehicle,” she said.
Light-skinned and round-faced, she waited politely in line, nursing her 2 month old while her 4 year old clung quietly to her shirt. Both daughters also had fevers.
After swallowing their malaria medicine, the family moved on to register with the measles team and be given an immunization record card kept in a laminated pouch. The cards include instructions for proper eating, the best defense against diseases like measles.
The cards are a kind of survival manual for the families, redesigned by the WHO specifically for the campaign with the hopes that families wouldn’t lose them. Successful large-scale vaccination requires good record-keeping, Feldon said.
The ploy worked. As villagers milled about a clearing near the pagoda after the examinations, they carried the attractive, bright pink or yellow cards close to them. One toddler was reprimanded harshly by his mother when he tried to pull the card from its plastic jacket.
While Preap Poa’s daughters were given their measles shots, she was inoculated for tetanus, another avoidable disease that threatens newborns. All women between the ages 15 and 44 are given these shots to prevent newborn infections. When the tetanus bacteria infects a baby, its jaws lock. Unable to suckle breast milk, the baby starves to death.
Finally, the daughters were given vitamin A supplements that will beef up the body’s supply for four to six months, protecting them from the harmful effects of both measles and malaria while the vaccine program is under way. They were also given packets of other vitamins to stay healthy.
Some of the children found these an immediate distraction, tasting one colored tablet and spitting it back up into the bag before trying the next.
Meanwhile, health workers struggled to educate these isolated people about the importance of health, vitamins and nutrition.
In under four hours, Preap Poa and her villagers had been diagnosed or treated for malaria, inoculated and handed chemically treated bed nets.
The campaign will continue like this for the next year, with remote villages across the country. Next year, phase two will begin with the closer, more populated areas.
The outlook for getting measles under control in the country is positive, even if the task seems overwhelming. Just four years ago, the maps showing recorded polio cases looked almost identical to the measles map now hanging in the EPI office: evidence of the disease was everywhere. In just five years, though, a heavy immunization program eradicated the disease, and in October, the entire South Pacific region, including Cambodia, was declared polio-free, Feldon said.
By mid-2002, Feldon said, the country should have “pretty good coverage” for measles. But there is still a lot of work between now and then. Many more field trips will have to be made, as well as follow-up trips to regions already visited. And until overall nutrition in the country improves, epidemics will threaten large populations.
“We’re not going to get there right yet,??” he said. But, he added, for a very low price, they eventually will be.
We’re not there yet, Feldon said, but eventually the problem can be overcome—and for a very low price.
Vitamin A capsules cost $0.02 apiece. Children need two per year. The immunization costs $0.10 per person. So, not including costs of transportation, the nation could be vaccinated for $0.14 a person per annum?.
“Considering the return on it,” he said, “it’s a very good investment.”