Researchers find that adult wild chimpanzees developed certain immunity against malaria parasites

May 28, 2013
This is a group of chimpanzees, Taï National Park, Cote d'Ivoire. Credit: Sonja Metzger

Wild great apes are widely infected with malaria parasites. Yet, nothing is known about the biology of these infections in the wild. Using faecal samples collected from wild chimpanzees, an international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the Robert Koch Institute in Berlin has now investigated the effect of the animals' age on malaria parasite detection rates. The data show a strong association between age and malaria parasite positivity, with significantly lower detection rates in adult chimpanzees. This suggests that, as in humans, individuals reaching adulthood have mounted an effective protective immunity against malaria parasites.

In malaria regions the parasite prevalence in the human body as well as malaria-related morbidity and mortality decrease with age. This reflects the progressive mounting of a . Researchers of the Max Planck Institute for Evolutionary Anthropology and the Robert Koch Institute now present a study which addresses the age distribution of infection in a group of wild chimpanzees.

To this end the researchers collected 141 faecal samples from seven female and 12 male wild chimpanzees from Taï National Park, Cote d'Ivoire. At time of sampling the animals' ages ranged between 3 and 47 years. The researchers extracted DNA from the faecal samples, analysed it and so identified the malaria parasite-positive samples. "In the course of this 2-month study almost every individual chimpanzee of the group was found positive at least once", says Hélène De Nys of the Max Planck Institute for Evolutionary Anthropology and the Robert Koch Institute. "Our data further suggest that at every point in time at least one individual of this chimpanzee group is infected".

Further analyses showed that malaria parasites were detected more often in younger than in older animals. Whether these were female or male, however, did not make a difference. "This is the first indication that epidemiological characteristics of malaria in wild chimpanzee populations might be comparable to those in human populations", says Roman Wittig of the Max Planck Institute for . "As in humans, the development of acquired immunity likely plays an important role in wild chimpanzees as well".

Throughout this process, malaria parasites might also contribute directly to decimating young chimpanzees. During analyses performed on more than 30 dead adult chimpanzees from the same community malaria could be excluded as the cause of death. For young chimpanzees, however, the question remains open. While it is known that mortality in young chimpanzees is high, their bodies are rarely accessible. This is because they are less likely to be found and because their carcasses are carried for several days by their mothers. "Even though at this stage, we cannot pinpoint pathogenicity of malaria parasites found in wild , our results suggest a continuous exposure of this population, leading to the development of a certain resistance to infection", says Fabian Leendertz of the Robert Koch Institute.

Explore further: Locusts provide insight into brain response to stimuli, senses

More information: Hélène M. De Nys, Sébastien Calvignac-Spencer, Ursula Thiesen, Christophe Boesch, Roman M. Wittig, Roger Mundry and Fabian H. Leendertz, Age-related effects on malaria parasite infection in wild chimpanzees, Biology Letters, May 29, 2013, DOI: dx.doi.org/10.1098/rsbl.2012.1160

Related Stories

Malaria: A vector infecting both apes and humans

May 03, 2013

In 2010, a study revealed that the main agent of malaria in humans, called Plasmodium falciparum, arose from the gorilla. Today, the vector which transmitted the parasite from apes to humans has just been i ...

Chimpanzees use botanical skills to discover fruit

Apr 10, 2013

(Phys.org) —Fruit-eating animals are known to use their spatial memory to relocate fruit, yet, it is unclear how they manage to find fruit in the first place. Researchers of the Max Planck Institute for ...

Recommended for you

Norway tests out 'animal rights cops'

12 hours ago

Norwegian police is creating a unit to investigate cruelty to animals, the government said Monday, arguing that those who hurt animals often harm people too.

High-pitched sounds cause seizures in old cats

14 hours ago

When the charity International Cat Care asked veterinary neurologists at Davies Veterinary Specialists, UK, for help with several enquiries it had received regarding cats having seizures, seemingly in response ...

Bumblebees use nicotine to fight off parasites

20 hours ago

Researchers from Queen Mary University of London (QMUL) and Royal Holloway, University of London (RHUL), gave bumblebees the option to choose between a sugar solution with nicotine in it and one without. ...

Two new iguanid lizard species from the Laja Lagoon, Chile

20 hours ago

A team of Chilean scientists discover two new species of iguanid lizards from the Laja Lagoon, Chile. The two new species are believed to have been long confused with other representatives of the elongatus-kriegi ...

User comments : 0

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.