Thursday, January 11, 2024

Hong Kong AFCD: 9th Farm Tests Positive for African Swine Fever

 

How ASF Spreads

#17,861

In a follow up to last week's report (see Hong Kong Reports 8th Pig Farm Infected With ASF), Hong Kong's AFCD (Agriculture, Fisheries & Conservation Department) today reports their 9th farm infected since last November. 

After smoldering in Eastern Europe and Russia for a decade, ASF arrived in China in the summer of 2018, and quickly spread across that nation killing as much as half of their pig population (see African Swine Fever In China: Epizootic or An EpicZootic?).

African Swine Fever (not to be confused with `swine flu') does not affect humans directly, but it does cause huge economic losses and contributes to food insecurity around the world. 

ASF is often spread - at least locally - via infected pigs and wild boars (or by infected ticks), but the virus can live for weeks or even months in infected food products, and exported pork products are believed to be a major cause of the international spread of African Swine Fever

Hong Kong has reported a few scattered detections of ASF in local pigs over the past 5 years - apparently imported from the mainland -  but has managed to quickly eradicate the disease each time (see 2019's Hong Kong: ASF Detected For A Second Time At Local Slaughterhouse).

This time, their outbreak has been harder to contain.  This report from the AFCD.

Wednesday, January 10, 2024

The Agriculture, Fisheries and Conservation Department (AFCD) today (January 10) announced that samples taken from a pig farm in Yuen Long had tested positive for the African Swine Fever (ASF) virus. The present ASF case has been discovered with the implementation of the new proactive emergency measure on handling dead pigs on local pig farms since January 3.

AFCD staff inspected a licensed pig farm in San Tin, Yuen Long on January 9 and collected 32 samples from pigs. Upon testing, one of the samples was found positive for the ASF virus. The AFCD has immediately suspended transportation of any pigs from the farm concerned until further notice according to the contingency plan on ASF. The AFCD is arranging culling of all pigs, totalling over 1 700 on the farm concerned, for the sake of prudence. The culling operation will commence this week.

Located within the 3-kilometre monitoring zone of a Yuen Long pig farm where ASF was previously detected, the index pig farm is adjacent to the farm where pig samples tested positive for the ASF virus in the end of last month. Upon AFCD's preliminary investigation and consultation with the international veterinary expert, it is believed that the pigs of the index farm were infected with the ASF virus earlier and now succumb to the disease as the incubation period can last up to 19 days.

The AFCD has implemented an emergency measure on handling dead pigs on local pig farms on the advice of an international veterinary expert since January 3. All farms are required to collect and submit to the AFCD nasal swab samples from pig carcasses for ASF virus testing. Disposal of carcasses can only be arranged by the farms upon confirmation of a negative result. The discovery of pigs infected with ASF on the index pig farm through the implementation of the new measure demonstrates that the measure can proactively curb the spread of the virus and effectively stop pigs infected with the ASF virus from leaving the farm, thereby interrupting the transmission of the virus among local pig farms.

An AFCD spokesman said, "Since the implementation of the enhanced measure, the situation of ASF on local pig farms has somewhat been alleviated. However, as the incubation period of the ASF virus can last up to 19 days, other pig farms locating within the 3-kilometre monitoring zone still present a higher risk of outbreaks. The AFCD will continue to closely monitor the situation of the pig farms and offer recommendations to enhance their biosecurity measures."

The spokesman further said, "The AFCD collaborated with the international veterinary expert to provide guidelines on biosecurity measures for local pig farms earlier. The AFCD will further explain and provide training to the industry to facilitate prompt implementation and strict observation of the biosecurity measures specific to their pig farms, thereby effectively containing the spread of ASF on local pig farms on different levels. Meanwhile, in order to strengthen the knowledge of local pig farmers of the clinical signs of ASF for early detection and reporting of abnormality of pigs, the AFCD has launched the Guidelines for Reporting Cases of African Swine Fever to assist pig farmers in identifying suspected cases for early reporting and to take appropriate follow-up. Sampling materials and protective clothing have been distributed to all local pig farms. Close communication is kept with pig farmers to update them on the latest situation of ASF via SMS groups."

The spokesman also said that positive cases should be seriously and promptly handled as the effect of ASF is very lethal to pigs. If the spread is not contained, a large number of pigs will die and hence seriously impacting pig farmers and the pig rearing industry. AFCD staff immediately notified all local pig farmers of this incident and reminded them to alert the AFCD immediately if abnormal health condition is observed in pigs.

The AFCD has sent staff to inspect the eight pig farms within 3 kilometres of the index farm. Five pig farms among these have no pigs currently. As for the remaining three pig farms, pig samples have been collected for ASF virus testing with negative test results. For the sake of prudence, the AFCD has temporarily suspended movements of pigs on those pig farms until further notice. No reports of abnormalities from pig farms outside the 3-kilometre zone have been received so far. AFCD staff are conducting visits in phases to all local licensed pig farms to ensure good biosecurity measures have been properly implemented; and continued close surveillance to detect pigs with abnormalities and if a farm is infected as early as possible. Surveillance of wild pig activities in the vicinity of the index farm has also been stepped up.

The spokesman stressed that ASF is not a zoonotic disease and will not infect humans, hence does not present any human health and food safety risk. Regardless of whether the pigs are infected with ASF, pork cooked thoroughly is safe for consumption. Members of the public do not need to be concerned.

The present case does not affect the operation of local slaughterhouses nor the overall supply of live pigs. Since June 2019, a daily clearance arrangement whereby live pigs will be slaughtered within 24 hours upon admittance has been imposed in Sheung Shui and Tsuen Wan slaughterhouses. Under the arrangement, lairages in different areas of the slaughterhouses will be cleared out and undergo thorough cleaning and disinfection every day to further enhance the biosecurity and minimise the risk of infection among pigs in the slaughterhouses.

The Food and Environmental Hygiene Department and the AFCD will continue to stringently conduct cleaning and disinfection of Mainland live pig transportation vehicles and their counterparts for local pigs at slaughterhouses to minimise the risk of cross-infection of ASF. Mainland live pig vehicles and local ones should be thoroughly cleaned and disinfected every time they leave the Sheung Shui Slaughterhouse (SSSH), and the respective designated positions for their cleaning and disinfection are separated. Manpower and equipment of the SSSH have been strengthened immediately for cleaning and disinfection of the vehicles. In light of these stepped-up measures, the slaughterhouses need not be closed and other pigs need not be culled.

As culling operation takes time, the AFCD will release updated operation information every day later on the departmental web page, www.afcd.gov.hk, for the public.

 

While the most recent FAO report on ASF In Asia (see map below) shows no reports from Mainland China, the Chinese government has a long history of suppressing reports of the disease (see here, here, and here).