Published Date: 2023-06-27 13:32:28 BST
Subject: PRO/AH/EDR> Foot & mouth disease - Malawi: cattle, st pending, WOAH
Archive Number: 20230627.8710805

FOOT & MOUTH DISEASE - MALAWI: CATTLE, SEROTYPE PENDING, WOAH

A ProMED-mail post http://www.promedmail.org
ProMED-mail is a program of the International Society for Infectious Diseases http://www.isid.org

Date: Mon 26 Jun 2023
Source: OIE-WAHIS (World Animal Health Information System) 2023 [edited]
https://wahis.woah.org/#/in-review/5099


Malawi, foot-and-mouth disease virus (inf. with)
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General information
Report type: immediate notification
Started: 12 Apr 2023
Confirmed: 28 Apr 2023
Reported: 24 Jun 2023
Reason for notification: recurrence
Last occurrence: 16 Feb 2023
Causal agent: foot-and-mouth disease virus
Subtype: pending
Nature of diagnosis: clinical, laboratory
This event pertains to a defined zone within the country.

Outbreak location 1: Chimkwita, TA Nsamala, Balaka
Date of start of the outbreak: 11 May 2023
Epidemiological unit: farm
Affected animals
Species / Susceptible / Cases / Deaths / Killed and disposed of / Slaughtered or killed for commercial use / Vaccinated
Cattle / 750 / 31 / 0 / 0 / 0 / 251

Outbreak location 2: Lobi, TA Pemba, Dedza
Date of start of the outbreak: 9 May 2023
Epidemiological unit: village
Affected animals
Species / Susceptible / Cases / Deaths / Killed and disposed of / Slaughtered or killed for commercial use / Vaccinated
Cattle / 18 262 / 12 / 0 / 0 / 0 / 0

Outbreak location 3: Lombe, TA Ngabu, Chikwawa
Date of start of the outbreak: 12 Apr 2023
Epidemiological unit: village
Affected animals
Species / Susceptible / Cases / Deaths / Killed and disposed of / Slaughtered or killed for commercial use / Vaccinated
Cattle / 702 / 32 / 0 / 0 / 0 / 9643

Affected population: cattle being grazed close to the national park known to harbor buffaloes

Epidemiology
Source of the outbreak(s) or origin of infection: contact with wild species, contact with infected animal(s) at grazing/watering points

Control measures
Domestic control measures applied: vaccination in response to the outbreak(s), quarantine, surveillance within the restricted zone, movement control, surveillance outside the restricted zone

Diagnostic test results
Laboratory name and type / Species / Test / Test date / Result
Botswana Vaccine Institute (BVI) / cattle / virus isolation / - / pending
Central Veterinary Laboratory, MWI / cattle / ELISA for the detection of antibodies against non-structural proteins (NSP ELISA) / 28 Apr 2023 / positive

[The location of the outbreaks can be seen on the interactive map included in the WOAH report at the source URL above.]

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Communicated by:
ProMED

[Foot-and-mouth disease (FMD) is endemic in Malawi. The following information is available from the WRLFMD-Pirbright Institute (https://www.wrlfmd.org/southern-africa/malawi):

"FMD virus serotype / Years
Untyped / 2015
O / 1957, 1962, 1974-1975, 1982, 1985, 1998, 2022
A / 1966-1967, 1973, 1974 (carrier cattle), 1981
SAT1 / 1970-1971, 2000-2001, 2015-2016, 2021
SAT2 / 1959, 1973, 1975, 2003-2004, 2008, 2011, 2019, 2020
SAT3 / 1976"

"All 3 SAT serotypes are probably endemic in the African buffalo (Syncerus caffer) population."

The following abstract is from an article titled "Spatio-temporal patterns and risk factors of foot-and-mouth disease in Malawi between 1957 and 2019" (see reference below):

Abstract:
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"Foot-and-mouth disease (FMD) is an important livestock disease causing short-term and long-term production losses and hindering local and international trade. To gain access to lucrative foreign markets and also improve local trade, there is a need to employ effective preventive and control strategies. Although FMD has been present in Malawi for over 60 years, little knowledge is available concerning the dynamics and drivers of FMD in the country. A modelling study based on retrospective data was conducted to establish the spatio-temporal distribution and determine the risk factors associated with FMD in Malawi. A retrospective space-time analysis was performed, and a matched case-control study was carried out to investigate risk factors. The number of reported FMD outbreaks has descriptively increased after 2000, and the disease has spread to previously unaffected areas. Two significant spatio-temporal clusters of FMD were identified: one in the southern region and the other in the northern region. An analysis of only index cases (1st detected locations) also detected 2 clusters with one in the northern region and the other in the southern region. Higher beef cattle density (p = 0.023), higher pig density (p = 0.043), and increased distance to wildlife protected areas (p = 0.036) were positively associated with the risk of FMD, while increased distances to international borders (p = 0.008) and roads (p = 0.034) were associated with reduced risk of FMD. High FMD risk areas were observed in the southern and northern regions but not in the central region during the early years (1957-1981). The more recent increase in FMD risk at the end of the study period (2019) in the central region might be attributed to increases in livestock density in this region. These findings provide insight into the pattern of FMD occurrence that will promote informed decisions for the progressive control of FMD in the region."

Reference:
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Chimera E T, Fosgate G T, Etter E M C, et al. Spatio-temporal patterns and risk factors of foot-and-mouth disease in Malawi between 1957 and 2019. Prev Vet Med. 2022; 204: 105639; doi: 10.1016/j.prevetmed.2022.105639. - Mod.CRD

ProMED map of Malawi: https://promedmail.org/promed-post?place=8710805,176]