SUMMARY
A yellow fever outbreak was detected in Angola late in December 2015 and confirmed by the Institut Pasteur Dakar (IP-D) on 20 January 2016. Subsequently, a rapid increase in the number of cases has been observed.
As of 11 May 2016, Angola has reported 2267 suspected cases of yellow fever with 293 deaths. Among those cases, 696 have been laboratory confirmed. Despite vaccination campaigns in Luanda, Huambo and Benguela provinces circulation of the virus in some districts persists.
Three countries have reported confirmed yellow fever cases imported from Angola:
Democratic Republic of The Congo (DRC) (39 cases), Kenya (two cases) and People’s Republic of China (11 cases). This highlights the risk of international spread through non-immunised travellers.On 22 March 2016, the Ministry of Health of DRC confirmed cases of yellow fever in connection with Angola. The government officially declared the yellow fever outbreak on 23 April. As of 11 May, DRC has reported three probable cases and 41 laboratory confirmed cases: 39 imported from Angola, reported in Kongo central province and Kinshasa and two autochthonous cases in Ndjili, Kinshasa and in Matadi, Kongo Central province. The possibility of locally acquired infections is under investigation for at least 10 non-classified cases in both Kinshasa and Kongo central provinces.
In Uganda, the Ministry of Health notified yellow fever cases in Masaka district on 9 April 2016. As of 11 May, 51 suspect cases and seven laboratory confirmed cases have been reported from three districts: Masaka, Rukungiri and Kalangala. According to sequencing results, those clusters are not epidemiologically linked to Angola.
The virus in Angola and DRC is largely concentrated in main cities. The risk of spread and local transmission to other provinces in the three countries remains a serious concern. The risk is high also for potential spread to bordering countries especially those classified as low risks for yellow fever disease (i.e. Namibia, Zambia) where the population, travellers and foreign workers are not vaccinated against yellow fever.
SURVEILLANCEAngola
From 5 December 2015 to 11 May 2016, the Ministry of Health has reported a total of 2267 suspected cases with 293 deaths and 696 laboratory confirmed cases. There are confirmed cases in 14 of the 18 provinces (Fig. 1) and suspect cases are present in all provinces. Local transmission is present in seven provinces, in 21 districts.
Seventy percent of these cases are reported in Luanda province (Fig. 2). Namibe province, bordering Namibia, recently reported confirmed cases and local transmission.Despite a decreasing trend (Fig. 3), the outbreak in Angola remains of high concern due to persistent local transmission in Luanda. Although vaccination efforts have reached more than seven million people, local transmission has been reported in six provinces (urban areas and main ports) and there is a high risk of spread to neighbouring countries.
The risk of establishment of local transmission in other provinces where no autochthonous cases are reported is high. DRC has reported cases imported from two provinces in Angola where no local transmission is currently reported (Cabinda and Zaire). Cabinda is an exclave and province of Angola and is separated from the rest of Angola by a narrow strip of territory belonging to the DRC and bounded on the north by the Republic of the Congo. This poses also a further risk of transmission in DRC and Republic of the Congo.