Pathfinder
Editor, Senior Moderator
WEEKLY BULLETIN ON OUTBREAKS
AND OTHER EMERGENCIES
Week 29: 17 - 23 July 2023
Data as reported by: 17:00; 23 July 2023
...
United Republic of Tanzania
Circulating Vaccine-derived Poliovirus type 2
1 Case
0 Deaths
0% CFR
2 Grade
EVENT DESCRIPTION
The Ministry of Health of Tanzania has notified the World
Health Organization of a case of circulating vaccine
derived poliovirus type 2 (cVDPV2) detected in a
23-month-old female child with acute flaccid paralysis
(AFP) on 17 July 2023 following laboratory confirmation.
The case patient, with an onset of paralysis on 26 May
2023, was detected in Sumbawanga Municipality, Rukwa
Region, Tanzania, following routine AFP surveillance for
poliomyelitis. The confirmation followed the collection
of two stool samples from the case patient on 30 and
31 May 2023, which were sent to a regional reference
laboratory at the Uganda Viral Research Institute (UVRI)
for laboratory testing.
Genomic sequencing analysis showed that the virus
isolate had undergone 15 nucleotide changes and is
genetically related to cVDPV2 circulating in South Kivu,
Democratic Republic of the Congo. Lake Tanganyika,
which forms a border between Tanzania and the
Democratic Republic of the Congo, is located west of
the Rukwa Region, indicating possible cross-border
infection in the area.
This is the first recorded case of cVDPV2 in Tanzania
since 2000, and the country has remained free from
wild poliovirus since reporting its last indigenous case in
1996. However, since 2022 the country has been actively
participating in a multi-country coordinated outbreak
response across East and Southern Africa subregions in
response to the detection of different strains of poliovirus
in these sub-regions. According to the 2022 WHOUNICEF
estimates of national immunization coverage in
Tanzania, the oral polio vaccine third dose (OPV3) and
the inactivated polio vaccine first dose (IPV1) coverages
were 88%, respectively.
PUBLIC HEALTH ACTIONS
The Ministry of Health of Tanzania, together with
its Global Polio Eradication Initiative partners, is
coordinating the response to the event.
A risk assessment is being implemented, led by the
Ministry of Health and supported by Global Polio
Eradication Initiative partners, along with a field
investigation and planning of appropriate response.
Enhanced surveillance for additional AFP cases
is being conducted in the affected areas. Routine
surveillance activities are also ongoing across the rest
of the country.
An analysis of population immunity levels with a
focus on subnational areas is being conducted to
identify under-immunized populations for targeted
interventions.
SITUATION INTERPRETATION
Tanzania has reported its first case of cVDPV2 after
several years of no cases and more than a year of
coordinated subregional response activities. The current
outbreak highlights the potential for cross-border spread
and importation of polio cases among populations with
suboptimal immunity levels. A swift response, including
enhanced surveillance and a reactive circumscribed
immunization campaign, will be needed to avert any
potential expansion of the outbreak.
...
https://apps.who.int/iris/bitstream/handle/10665/371956/OEW29-1723072023.pdf
AND OTHER EMERGENCIES
Week 29: 17 - 23 July 2023
Data as reported by: 17:00; 23 July 2023
...
United Republic of Tanzania
Circulating Vaccine-derived Poliovirus type 2
1 Case
0 Deaths
0% CFR
2 Grade
EVENT DESCRIPTION
The Ministry of Health of Tanzania has notified the World
Health Organization of a case of circulating vaccine
derived poliovirus type 2 (cVDPV2) detected in a
23-month-old female child with acute flaccid paralysis
(AFP) on 17 July 2023 following laboratory confirmation.
The case patient, with an onset of paralysis on 26 May
2023, was detected in Sumbawanga Municipality, Rukwa
Region, Tanzania, following routine AFP surveillance for
poliomyelitis. The confirmation followed the collection
of two stool samples from the case patient on 30 and
31 May 2023, which were sent to a regional reference
laboratory at the Uganda Viral Research Institute (UVRI)
for laboratory testing.
Genomic sequencing analysis showed that the virus
isolate had undergone 15 nucleotide changes and is
genetically related to cVDPV2 circulating in South Kivu,
Democratic Republic of the Congo. Lake Tanganyika,
which forms a border between Tanzania and the
Democratic Republic of the Congo, is located west of
the Rukwa Region, indicating possible cross-border
infection in the area.
This is the first recorded case of cVDPV2 in Tanzania
since 2000, and the country has remained free from
wild poliovirus since reporting its last indigenous case in
1996. However, since 2022 the country has been actively
participating in a multi-country coordinated outbreak
response across East and Southern Africa subregions in
response to the detection of different strains of poliovirus
in these sub-regions. According to the 2022 WHOUNICEF
estimates of national immunization coverage in
Tanzania, the oral polio vaccine third dose (OPV3) and
the inactivated polio vaccine first dose (IPV1) coverages
were 88%, respectively.
PUBLIC HEALTH ACTIONS
The Ministry of Health of Tanzania, together with
its Global Polio Eradication Initiative partners, is
coordinating the response to the event.
A risk assessment is being implemented, led by the
Ministry of Health and supported by Global Polio
Eradication Initiative partners, along with a field
investigation and planning of appropriate response.
Enhanced surveillance for additional AFP cases
is being conducted in the affected areas. Routine
surveillance activities are also ongoing across the rest
of the country.
An analysis of population immunity levels with a
focus on subnational areas is being conducted to
identify under-immunized populations for targeted
interventions.
SITUATION INTERPRETATION
Tanzania has reported its first case of cVDPV2 after
several years of no cases and more than a year of
coordinated subregional response activities. The current
outbreak highlights the potential for cross-border spread
and importation of polio cases among populations with
suboptimal immunity levels. A swift response, including
enhanced surveillance and a reactive circumscribed
immunization campaign, will be needed to avert any
potential expansion of the outbreak.
...
https://apps.who.int/iris/bitstream/handle/10665/371956/OEW29-1723072023.pdf