Date: Fri 15 Jun 2018
Source: WHO Regional Office for Africa, Health Information and Risk Assessment [edited]
Weekly bulletin on outbreaks and other emergencies week 24: [11-17 Jun 2018; data as of 15 Jun 2018]
Liberia: 2930 cases, 14 deaths, 0.5 percent CFR
Liberia has been experiencing recurrent measles outbreaks since the beginning of 2018. In week 23 (week ending 10 Jun 2018), a total of 61 new suspected measles cases (with no deaths) were reported from 13 out of the 15 counties in the country, compared to 72 new cases reported in week 22 [week ending 3 Jun 2018]. 23 blood specimens collected from the suspected cases have been shipped to the National Reference Laboratory, while 20 of the case-patients had epidemiological links to confirmed cases. During the reporting week, 14 out of 92 health districts (in 5 counties) attained measles epidemic threshold of 3 laboratory confirmed cases. The 5 counties are Grand Bassa, Margibi, Maryland, Montserrado, and Nimba.
Between week 1 and week 23 of 2018 [1 Jan-10 Jun 2018], a total of 3086 suspected measles cases were reported. Of these, 177 were laboratory confirmed, 1762 had epidemiological links to confirmed cases, 562 were clinically compatible, 156 were discarded (after testing negative), and test results for 429 cases were pending. Of the 2930 confirmed, epidemiologically linked, clinically compatible, and suspected cases, 14 have died, giving a case fatality rate of 0.5 percent in this group; 558 (19 percent) were vaccinated, 334 (11 percent) were not vaccinated and 2 038 (70 percent) had unknown vaccination status. About 39 percent of the affected people are 4 years of age and below, 25 percent are between 5 and 9 years and 36 percent are 10 years and above.
Public health actions
The Ministry of Health Expanded Program on Immunization and the National Public Health Institute of Liberia (NPHIL) are coordinating response activities to the measles outbreak, with support from WHO, UNICEF, and other partners. The national epidemic preparedness and response committee (NEPRC), under the leadership of NPHIL and with technical support from WHO, UNICEF, US-CDC and other agencies, have been meeting weekly to review the measles outbreak situation and provide technical support to sub-national level. WHO has deployed the Polio STOP team in the 15 counties to support sub-national level response.
A nation-wide measles immunization campaign has been conducted across the country in 3 phases since 15 Feb 2018, targeting a total of 654 803 children aged 6-59 months. Preliminary data indicates that 97 percent (63 350) of the targeted populations were vaccinated across the country.
Active search for measles cases continues throughout the country and has been reinforced in districts and communities with sustained outbreaks. Epidemic threshold is monitored weekly across the country through routine data collection and analysis.
All measles cases are being provided with symptomatic management along with a high dose of vitamin A.
The National Public Health Reference Laboratory has been testing samples reported across the country, by serology (IgM detection), and routinely releasing test results.
Communities have been provided with education to seek early care for measles cases at the nearest health facility. Communities have also mobilized through town criers, radio messaging, and posters to ensure high coverage of the immunization campaign among targeted age group.
Liberia has been experiencing recurrent measles outbreaks since the beginning of the year . The reason for these outbreaks is known: the accumulation of a large number of susceptible populations over the years due to suboptimal immunization coverage. It is concerning that measles incidence cases are occurring in spite of the 3 phases of mass immunization campaigns conducted since February 2018, with seemingly high administrative coverage. The national authorities and partners need to drastically and speedily reduce the number of susceptible individuals in the most affected age-groups, maintain the build-up of vulnerable individuals at very low levels by immunising a large proportion (over 95 percent) of each new birth cohort and implement additional vaccination activities to periodically protect susceptible individuals who have accumulated.
With the well-developed immunization programme, structures, and systems, such measles outbreaks should be predicted and adequate preparedness measures put in place. Additionally, each measles outbreak should be followed by thorough evaluation of the cause of the outbreak, the surveillance system for early outbreak detection, the preparedness measures preceding the outbreak and the management of the outbreak, and an overall review of immunization programme goals and operations.
[A map showing the geographical distribution of measles cases in Liberia, week 1-23, 2018 can be seen at the source URL above. - ProMED Sr.Tech.Ed.MJ]
[HealthMap/ProMED-mail map of Liberia: