Potential transmission routes of SARS-CoV-2 from animals and animal products are shown in Fig. 2. While SARS-CoV-2 does not cause food borne illness, the virus has caused enormous disruptions to the global food supply chain. The risk of SARS-CoV-2 to food safety was detailed elsewhere . Animal product industries usually rely on the presence of metallic surfaces and the maintenance of low humidity and low temperature . However, these conditions can be favorable for the viability and transmissibility of SARS-CoV-2. While there was a significant reduction and exponential decay in the infectious titer, SARS-CoV-2 remained viable in aerosols for up to 3 h, on plastics for up to 72 h, and on stainless steel for up to 48 h after application . The viability of the virus on different environmental surfaces is shown in Table 1. In addition to rapid work speed and multiple long shifts, food industry workplaces tend to be very crowded with employees in close proximity to one another. Additionally, because of the loud mechanical noise, workers tend to talk louder or shout. These factors can increase the chances of the transmission of SARS-CoV-2 to the co-workers. In many industries, there is a significant number of younger employees. If the manpower in food industry mainly consists of youthful workforce, there can also be a high possibility of having an infected asymptomatic employee who could infect other employees. Infectious bronchitis is an avian disease caused by infectious bronchitis virus, a member of genus Gammacoronavirus in the family Coronaviridae, and is a major respiratory disease of poultry affecting lungs, kidney,drying cannabis and the reproductive tract and causing tremendous economic losses in the poultry industry worldwide . It causes multiple characteristic consequences such as kidney damage, decreased egg production, and deteriorated egg quality .
Another significant problem of infectious bronchitis is its rapid spread. Within 48 h, the whole flock can be infected and remains as a reservoir, even after recovery. The infection usually spreads horizontally from hen to hen, but not from hen to chick. It is still possible that the infection gets transmitted via contaminated eggshells in the hatcheries . Although chickens are not known to be infected with SARS-CoV-2 through the intranasal route, COVID-19 can still have economic negative impacts on the poultry industry . Different poultry species are susceptible to coronaviruses infections leading to the development of enteric diseases, respiratory diseases, and kidney diseases. Examples include turkey infected with Turkey coronavirus , quail infected with Quail coronavirus , guineafowl infected with Guineafowl coronavirus , and pheasant infected with Pheasant coronavirus .Porcine coronaviruses belong to four genera: Alphacoronavirus, Betacoronavirus, Gammacoronavirus, and D . The porcine epizootic diarrhea virus and the transmissible gastroenteritis virus are alphacoronaviruses of swine which infect epithelial cells of the gastrointestinal tract. Another alphacoronavirus named the porcine respiratory coronavirus has no affinity to the gastrointestinal tract. A fourth alphacoronavirus is swine acute diarrhea syndrome coronavirus , which causes acute diarrhea syndrome in piglets. A betacoronavirus is porcine haemagglutinating encephalomyelitis virus , while a deltacoronavirus is porcine deltacoronavirus . Due to similarities in protein characteristics, swine can be potential reservoir for the transmission of SARS-CoV and SARS-CoV-2 . PDCoV is an emerging swine pathogen. Importantly, it was recently detected from three sick Haitian children and is now recognized as a zoonotic pathogen .Coronaviruses of ruminants include bovine coronavirus which infects cattle, sheep, goat, buffalo, llamas, alpacas, and can cause respiratory distress . Examples include bubaline coronavirus that infects water buffalo, alpaca coronavirus that infects alpaca, and dromedary camel coronavirus that infects camels .
In addition, MERS-CoV causes infections in respiratory tracts of camels. The seroprevalence of MERS-CoV in dromedaries was reported to be more than 90% in different countries in Africa, Asia, and the Middle East . There is not enough evidence to suggest that cattle might have play a role in the COVID-19 pandemic. In a study on six animals, only two cattle tested positive for the virus in nasal swabs and showed specific seroconversion, indicating low susceptibility of cattle to SARS-CoV-2 infection . However, close contact of infected humans with large numbers of cattle may still lead to anthropozoonotic infections in cattle . The reason for the low susceptibility to infection is the low expression of ACE2 in the respiratory tracts of these ruminants . The SARS-CoV-2 outbreak in December, 2019 has been linked to Huanan Seafood Market in Wuhan, China . A second wave in June 2020 has been traced to Xinfadi Seafood Market in Beijing, China . Frozen seafood items contaminated with SARS-CoV-2 have been reported in China . Salmon-attached SARS-CoV-2 stayed in a viable status for at least 8 days at 4 ◦C, and 2 days at 25 ◦C . It is noteworthy that at 4 ◦C is the temperature of refrigerators, cold rooms, and transport carriers for storage of fish before selling in the fish or seafood market. Thus, the import and export of frozen and refrigerated fish can be a source of transmission of fish-attached SARS-CoV-2 across countries and continents. Imported frozen cod package surfaces from China showed signs of contamination by SARS-CoV-2 . This calls for strict inspection measures for the detection of SARS-CoV-2 in imported and exported fish during the pandemic . Evidence suggests that cold-storage foods may present a risk for the transmission of SARS-CoV-2 between different countries . Ferrets and cats have been shown to be permissive to infections with SARS-CoV-2 .
Cats were also susceptible to airborne transmission . SARS-CoV-2 infection has also been reported in dogs, tigers, and lions . Other susceptible species include mice, golden hamsters, minks, and non-human primates . Clinical signs in ferrets involved fever and loss of appetite . Both cats and non-human primates were asymptomatic . The main features of animals experimentally infected with SARS-CoV-2 are presented in Table 2. The supply chain of animal feed raw materials has been negatively impacted due to animal movement restrictions resulting from the pandemic-triggered lock downs. Regular patterns of production, supply, and consumption were severely disrupted . Thus, farm animals have been deprived from important feed ingredients in their diets. It has been reported that more than dairy farms have faced shortages of dry feed intake in Pakistan as a result of the pandemic . International cessations in exports and imports of animals’ feeds hampered the supply of several basic raw ingredients that are important for raising and fostering livestock . These raw ingredients include mixtures of carbohydrates, proteins, fats, minerals, and vitamins. As an example, Argentina-the world leader in soybean meal exports – had to reduce its exports of soybean, a critical feed ingredient, by half into feed manufacturing factories . Similarly, Brazil and U.S. have also faced hurdles in their soy meal and corn exports . Local restrictions have been impacted animal feed ingredients, as evidenced by pastoralists in African dry lands who were unable to feed their animals, typically fed on natural plants . International and local restrictions have naturally led to increased costs of animal feed materials, which impacted animal farms in different countries. In Bangladesh, there has been a 3.7% hike in dairy feed price . In India and many regions in Africa, the prices of key animal feed ingredients have increased by 15% as a result of the pandemic . In the United Kingdom, the prices of soy meal, wheat, corns, molasses,curing cannabis and other important animal feed stuffs have increased due to COVID-19 . The COVID-19 pandemic has jolted the livestock production. Pivotal livestock farming materials have been largely unavailable. These include frozen semen aliquoted in a semen straw for artificial insemination of livestock, replacement stocks , equipment , and animal feed additives , 2020. Veterinary healthcare services and other animal health preventative services have been greatly reduced during the pandemic . This caused significant delays in diagnosis and treatment of diseases. The reductions and delays resulted in halting the progress in prevention, control, and eradication of different animal and zoonotic diseases. Since zoonotic disease can also impact humans, the pandemic-triggered disruptions jeopardized human health in addition to animal health.
Furthermore, COVID-19 has negatively impacted food safety inspections, animal health extension services, and disease surveillance efforts which were important checks to prevent the spread of zoonotic diseases and other infections that impact human and animal health . This can create ripe conditions for future outbreaks and pandemics that can be detrimental to livestock health and human health . Amid the COVID-19 situation, markets have been disrupted throughout the world which ultimately affected animal production . The closure of animal markets and restrictions on export and import operations have deprived livestock producers from precious local and global marketing opportunities . In addition, intermediaries who collect animals and animal products and then process or sell them after fattening have been hit hard, which caused farmers to lose their links to major buyers . Thus, there was a sharp decline in animal processing and slaughtering capacities which further added to the turmoil in the livestock market . This has impacted both animals and animal products such as milk, eggs, and meat. Some farmers had to cull their animals or dump their animal products such as milk, which caused them significant income losses. According to the FAO, these losses have been especially severe on women who were unable to obtain the necessary nutrients for their small ruminants and poultry . The wide scale market disruption that resulted from the pandemic has impacted the agricultural workforce and caused staff shortages and layoffs in the labor force associated with animal production . There is a significant proportion of migrant workers in the livestock industry and meat plants . Many of them had to return to their home countries due to the lock downs, closures, and other measures that were implemented during the pandemic . During the peak of the pandemic, China closed livestock and poultry trading and slaughter markets in most of the nation, which results in labor shortage in slaughterhouses . Other causes for labor shortage include childcare, quarantine, and sick leave, which led to a 30% absence rate in some slaughterhouses in France and to similar issues in other countries in Africa and Asia . Owing to these factors and to other factors, the process of bringing animals and animal products to local or global markets faced multiple hurdles. The problem of labor shortage has had significant impacts on countries in South and Southeast Asia. In India, labor shortage has led to 23% food grain production loss . Labor shortage has also led to food insecurity concerns and hunger concerns for daily wage workers in the farm and non-farm sectors in Bangladesh . Food insecurity has also emerged as a major pandemic-related concern in Nepal and other countries . The worldwide demand for meat has been increasing in recent years for many factors including the rapid growth of population in many parts of the world . However, working in slaughterhouses and meat packing plants has been considered a major risk for COVID-19 infection during the pandemic . Workers in meat plants and slaughterhouses in Germany, England, Wales, and Portugal have reportedly been infected with SARS-CoV-2. . The Portugal outbreak led to short-term closure of the poultry slaughterhouse and the implementation of strict hygienic measures including health screening of all employees, adding new bathing areas, and replacing old disinfectants with stronger ones . Previous reports confirmed the presence of rotaviruses and coronaviruses in raw milk and dairy products . MERS-CoV has been shown to survive for prolonged periods in milk . The microbial composition of milk is influenced by the hygienic conditions of the animal, the animal’s feed and water, air quality, environment, and equipment used for milking . To minimize transmission of food borne pathogens, milk and dairy products are subjected to the process of pasteurization . Although some studies suggested that SARS-CoV-2 can spread via food products as it can remain viable on inanimate surfaces for hours to days , there is no proof that SARS-CoV-2 can spread directly through food, milk, milk products, or eggs . However, it is always a good practice to understand the sources of contamination of dairy products and to try to minimize all possible routes of contamination . The COVID-19 pandemic caused global economic losses and significant negative impacts on the agri-food sector, including farming, crop production, and animal production systems .