Peste des petits ruminants

Current epidemiological situation

Since the late 1990s, the geographic spread of the disease, with the emergence of PPR outbreaks in countries which had been disease-free, and re-emergence in countries and zones known to be enzootic, has radically changed the situation.

(Click on the maps to enlarge them).

Epidemiological surveillance has revealed that lineage IV is continuing to spread in Asia in an easterly direction, but is also extending west and invading Africa, where it is becoming the dominant lineage.

  • In 2000, it was discovered in Sudan, in East Africa, where it cohabitated with the native lineage III and passed into a new host, the dromedary.

  • It then spread to Egypt and across North Africa, finally reaching Morocco in 2008.

  • Today (2015), lineage IV is present across North Africa with the exception of Morocco, which succeeded in eradicating the disease through mass vaccination campaigns.

  • It also is circulating in the northeast of Africa (Sudan and Eritrea) and in Central Africa (Cameroon, Central African Republic, Uganda) where it coexists with lineage II.

  • The most recently infected African countries, Angola and Comoros, are an indicator of its spread from the north to the south of Africa.

A similar phenomenon occurred in West Africa with lineage II, today alone present in Senegal, having taken the place of lineage I.

Note

These upheavals in the distribution of lineages must be interpreted cautiously as epidemiological data collected in the field remains very incomplete due to inadequate surveillance. While the link between animal mobility and the spread of the virus is now certain, it cannot alone explain the dominance of lineage IV in West and Central African countries which have no tradition of small ruminant exchanges with countries east of the Red Sea. One answer may be found in the capacity of PPRV to adapt its pathogenicity to selective changes in its environment, notably to the different susceptibility of its different hosts.

PreviousPreviousNextNext
HomepageHomepagePrintPrint CIRAD CMAEE-FVI - 2016 Attribution – Non commercial - No Derivative WorkCreated with Scenari (new window)