Despite an exhaustive vaccination campaign - one which has used up so much of the existing vaccine stockpile that it has the WHO ready to propose smaller doses (STAT News) - parts of Africa are still seeing their worst Yellow Fever outbreak in decades.
What started in Angola late last year has spread to several neighboring countries, and a small number of exported cases have turned in places like China, raising concerns of international spread.
Three months ago the ECDC issued a rapid risk assessment on the Angola outbreak (see Yellow Fever In Angola & The Risk Of International Spread - ECDC), which warned:
As yellow fever and dengue fever share the same mosquito vector, Aedes aegypti, any area where dengue has been transmitted could be suitable for establishment of local transmission of yellow fever if the virus is introduced by a viraemic traveller.
Theoretically, this shouldn't be much of a problem, as countries with competent vectors (Aedes mosquitoes) are supposed to require a yellow fever vaccination for travelers going to or returning from areas were the virus is endemic.
But some countries appear to have been less than diligent in enforcing this requirement, and fake Yellow Fever vaccination certificates are reportedly pretty common (see ABC news Yellow fever deaths in Angola linked to false vaccination documents).
Today the ECDC has published a new, updated epidemiological update, which includes reports from Angola, the DRC, Congo, Ethiopia, and Ghana in Africa, and Peru in South America.
I've only include some brief excerpts, follow the link to read:
Epidemiological update: Outbreak of yellow fever in Angola
13 Jun 2016
An outbreak of yellow fever started in December 2015 in the municipality of Viana, Luanda province, and has since spread to all provinces of Angola. A rapid increase in the number of suspected cases has been recorded since mid-January 2016. As of 3 June 2016, the Angolan Ministry of Health has reported 2 954 cases and 328 deaths. These figures represent an increase of 687 cases and 35 deaths since the last epidemiological update on 8 May 2016. Of those cases, 819 are confirmed, including 482 from Luanda. Since 8 May, Luanda has reported 37 new confirmed cases. Confirmed cases have been reported in 16 of the 18 provinces in Angola while suspected cases have been reported in all provinces. Namibe province, which was newly affected at the beginning of May 2016, now reports two confirmed cases and ten suspected cases.
Yellow fever cases among travellers from Angola have been reported in China (11 cases), Democratic Republic of the Congo (56 confirmed cases) and Kenya (two cases).
More than ten million people in Angola have been vaccinated through a large-scale campaign that has been running since the beginning of February. The vaccines have been mobilised through the yellow fever vaccine emergency stockpile that is made available through the International Coordinating Group for Vaccine Provision, with support from Gavi, the UN Central Emergency Response Fund, and a vaccine donation from Brazil.