Increasing and accurately measuring rabies vaccination coverage in Tanzania

December 3, 2015

Canine mediated rabies is endemic in Tanzania despite the fact that the disease can be prevented entirely by mass dog vaccination. Since 2003 the Serengeti Health Initiative has been carrying out rabies vaccination campaigns that aim to achieve the 70% coverage required in order to eliminate rabies. The research team, a partnership among the Nelson Mandela African Institution of Science and Technology, the Paul G. Allen School for Global Animal Health at Washington State University, and Chicago's Lincoln Park Zoo, studied whether the use of incentives might increase owner participation in the vaccination events, and also examined the most effective way to estimate post-vaccination coverage.

Sixty-two villages were randomly allocated to either a control (no incentives) or one of three incentives: bright colored collars given to the dogs, bright colored wristbands given to the owners and both collars and wristbands handed out. Dog owners were also asked to rate which incentive they preferred. On average, the incentives resulted in 34 more dogs brought for vaccination treatment per village, with no difference seen between the different types of incentives. Given the increase in dog turnout, the researchers estimated the mean reduction in the cost-per-dog and the price-threshold under which the cost of the incentive used must fall to be economically viable. This was $0.47. From the surveys, 41% indicated a preference for the dog collars and 43% for wristbands. 98% of respondents liked the incentives and were happy to see that vaccinated and non-vaccinated dogs could be easily distinguished.

The researchers also tested the accuracy of the two methods normally used to determine . They tested them against the gold-standard of a village-wide census which, while accurate, is far more expensive than the commonly-used methods of random household questionnaire and transect survey. For the household questionnaire, a locally recruited interviewer was used to facilitate a verbal questionnaire at a minimum of 70 houses per village. For the transect survey, vaccinated dogs were marked with a stripe of water-soluble purple spray. The day following the vaccination, the teams performed a drive through the village estimating the proportion of marked and unmarked dogs. The household questionnaire underestimated coverage by 6.6% while the transect survey overestimated by 7.1%. These estimates were not significantly different from the results of the village-wide census (p = 0.14 and 0.06 respectively).

A reliable method of assessing post-vaccination coverage is vital to check if the elimination coverage of 70% is met. In view of this, the researchers recommend the use of the household questionnaire to give a conservative estimate, particularly as it is more likely to pick up vaccination of puppies. The use of incentives is also recommended, to alert and remind villages to take their dogs to the vaccination centers, as well as providing a way of distinguishing vaccinated and non-vaccinated .

The study is published today in PLOS Neglected Tropical Diseases.

Explore further: Every nine minutes, someone in the world dies of rabies

More information: PLOS Neglected Tropical Diseases, dx.plos.org/10.1371/journal.pntd.0004221

Related Stories

Every nine minutes, someone in the world dies of rabies

October 1, 2015
A human death from rabies is a tragic but rare thing in the United States and most developed nations. It's just as tragic but sadly common in parts of the world where some 3 billion people are at risk of being bitten by a ...

Agonizing rabies deaths can be stopped worldwide

September 25, 2014
The deadly rabies virus—aptly shaped like a bullet— can be eliminated among humans by stopping it point-blank among dogs, according to a team of international researchers led by the Paul G. Allen School for Global Animal ...

European rule changes on cross border pet transport may heighten rabies risk

June 25, 2015
Recent changes to regulations on the transport of pets across Europe may have increased the threat of introducing rabies from rescue dogs into countries considered free of the disease, suggests research published in Veterinary ...

Recommended for you

How hepatitis C hides in the body

October 13, 2017
The Hepatitis C (HCV) virus is a sly enemy to have in one's body. Not only does it manage to make itself invisible to the immune system by breaking down communication between the immune cells, it also builds secret virus ...

Largest study yet of malaria in Africa shows historical rates of infection

October 12, 2017
(Medical Xpress)—A team of researchers with members from the Kenya Medical Research Institute, the University of Oxford and the University of KwaZulu-Natal has conducted the largest-ever study of the history of malaria ...

Promising new target for treatment of psoriasis is safe, study shows

October 11, 2017
A protein known to play a significant role in the development of psoriasis can be prevented from functioning without posing a risk to patients, scientists at King's College London have found.

Norovirus evades immune system by hiding out in rare gut cells

October 11, 2017
Noroviruses are the leading cause of non-bacterial gastroenteritis in the world and are estimated to cause 267 million infections and 20,000 deaths each year. This virus causes severe diarrhea, nausea, and stomach pain.

Research reveals how rabies can induce frenzied behavior

October 11, 2017
Scientists may finally understand how the rabies virus can drastically change its host's behavior to help spread the disease, which kills about 59,000 people annually.

Experimental Ebola vaccines elicit year-long immune response

October 11, 2017
Results from a large randomized, placebo-controlled clinical trial in Liberia show that two candidate Ebola vaccines pose no major safety concerns and can elicit immune responses by one month after initial vaccination that ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.