Published Date: 2021-08-14 17:22:20
Subject: PRO/AH/EDR> Foot & mouth disease - Namibia (02): (CA) cattle, st O
Archive Number: 20210814.8595516

FOOT & MOUTH DISEASE - NAMIBIA (02): (ZAMBEZI) CATTLE, SEROTYPE O

A ProMED-mail post http://www.promedmail.org
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Date: Sat 14 Aug 2021
Source: Xinhua via CGTN (China Global Television Network) [edited]
https://africa.cgtn.com/2021/08/14/namibia-detects-new-foot-and-mouth-disease-virus-strain/


Namibia has detected a new strain of foot-and-mouth disease (FMD) virus, [serotype] O, in its northeast Zambezi region, an official said Friday [13 Aug 2021].

According to Agriculture Ministry Chief Veterinary Officer Albertina Shikongo, the new strain is more contagious, adding that despite the high vaccination coverage at about 90%, new cases of the disease continue to be observed in vaccinated herds.

"This is the 1st time in history that the FMD virus [serotype] O is being identified [in Namibia]. The high infection rate caused by the new FMD [serotype] O explains the poor response to the vaccination to this outbreak," she said.

Shikongo said further investigations to establish the source of the new strain are ongoing. However, she added that "it is suspected the strain is a result of illegal cross-border movement of cattle between Namibia's Zambezi region and Zambia."

Namibia has since declared 4 constituencies as infected areas while the entire Zambezi region has been declared as a disease management area while movement of cloven-hoofed animals as well as potentially infectious commodities in and out of restricted areas has been banned.

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[According to Namibia's country report on the website of FMD's World Reference Laboratory (WRLFMD), Pirbright, presenting data obtained since 2007, (only) the following 3 FMDV strains have been serotyped and genotyped as of 2020 (years of detection, in parentheses): SAT1 (2015), SAT2 (2007, 2008, 2015, 2016), and SAT3 (2019, 2020). For further details, including links to the genotyping results, please see https://www.wrlfmd.org/southern-africa/namibia#panel-3482.

The outbreak addressed in the above report, serotyped O, is likely the one reported by Namibia to the OIE on 1 Jul 2021 from Katim Mulilo, northeast Zambezi (map at <tinyurl.com/y3btnct2>), which had started on 1 Jun 2021. At the time of reporting, the serotyping was pending; see 20210703.8494016, which included the following commentary by Mod.CRD:

"Namibia contains 3 FMD zones:
- FMD Infected zone
- FMD Free zone
- FMD Containment zone

"The Zambezi region is called the FMD Infected zone due to periodic occurrence of FMD in this region. The Zambezi region forms part of the Kavango-Zambezi Transfrontier Conservation Area (KAZA), and the presence of African buffalo, which is the carrier of FMD, makes control of this disease in this region very difficult" (https://www.nammic.com.na/index.php/library?task=download.send&id=66&catid=43&m=0).

According to the document referenced by Mod.CRD ("FMD and the Control Thereof in the Northern Communal Area of Namibia"; URL above), a "new" vaccine must be produced for every new outbreak of FMD. Because FMDV serotype O had not been recorded earlier in Namibia, the routinely applied vaccines have, probably, not included this strain and consequently Namibia's cattle are likely to be fully susceptible to it. Only one laboratory, the Botswana Veterinary Institute, is manufacturing regional FMD vaccines. - Mod.AS

HealthMap/ProMED map of Zambezi Region, Namibia: http://healthmap.org/promed/p/35623]