Meat is one of the foods of animal origin that is popular, nutritious, highly valued and priced.
Interestingly, the food is nutritious for humans and bacterial micro-organisms as well; making it a concern for health as a source of infection.
In food science, meat is used in the plural as “meats” when referring to meat from different kinds of animals collectively.
Red meats are less supportive of bacterial growth than white. Red meats are from animals like cattle, sheep, camel and goats while white are from rabbits, fish, birds, reptiles, amphibians, crustaceans and mollusc.
Due to their ease of decomposition, white meats are more likely to cause food poisoning than red meats. It is for this reason that on a picnic, those eating packed chicken sandwiches may get food poisoning while those feasting on beef ones may not as easily get ill.
However, all meats should be preserved properly as they may easily cause food poisoning.
Growth of micro-organisms on meat causes rotting, emission of a foul smell and bad taste that alerts someone the meat is spoilt.
Some bacteria produce very potent toxins that cause illness even in small quantities before there is detectable odour.
The meat may also be contaminated by few bacteria, which continue to multiply inside the body once swallowed and build up to numbers that can cause illness.
That is a reason one would not have noticed bad odour or taste in most food poisoning.
I recall one of my friends who got food poisoning from chicken. He said he must have been very hungry or his tongue and nose were not working properly because he never detected any bad taste or smell in the food.
Last week, I had a number of people asking why meat is being portrayed as dangerous food.
Some thought it was a conspiracy to discourage people from eating meat.
The inquiries were triggered by the rising number of media reports on lab evidence of contamination of meat with bacteria. The most recent ones were from Kenya and the United States.
They quoted independent scientific surveys of retail outlets in the two countries by reputable researchers and institutions.
Both studies reported on contamination of meat by bacteria and the confirmation that a portion of the micro-organisms were resistant to some drugs commonly used to treat infections in humans and animals.
The studies looked for the occurrence of the Escherichia coli (E. coli) bacteria that is conventionally used to test the presence of bacteria in food and water.
In both studies, some of the bacteria were resistant to tetracycline, penicillin, streptomycin, sulphonamide and trimethoprim.
These are commonly used drugs in veterinary and human drug formulations.
The US study went further and explored the genetic relationship between the bacteria the researchers found in the meat and those that caused serious disease in patients with urinary tract infections.
The US researchers found that some bacteria infecting humans had genes that indicated they had emanated from bacterial families found in the meat.
The researchers, therefore, concluded meat was a source of human urinary tract bacterial infections.
The big question for this study arises on how bacteria in meat would cause infection of the urinary tract in humans.
The most logical explanation is that meat handlers may have contaminated their hands with the bacteria from the meat and transferred the micro-organisms to their urinary tracts due to poor hygiene practices.
Epidemiologists, the scientists who study methods of disease transmission, should research more on the findings of the US study to determine how the bacteria are transferred from meat to people’s urinary tracts.
The findings of the two studies and many others confirm that meat can be a source of micro-organisms that may cause disease in humans.
The main cause of microbial resistance to medicine is the inappropriate use of drugs in animals and humans.
This has brought out a phenomenon called antimicrobial resistance and threatens to render commonly used antimicrobials ineffective in treating commonly occurring diseases in humans and animals.
The drugs to which some E. coli bacteria were found to be resistant to in the two studies are used in animals and humans.
In my experience, for instance, tetracyclines are rarely effective in treating E. coli mastitis in cattle. E. coli is a widely distributed bacteria and is found in the intestines of animals, including humans.
Most strains of the bacteria cause no disease but few, especially the O157 strain, causes severe disease in humans and animals in the intestines, respiratory and urinary tracts.
Meat gets contaminated with bacteria mostly during slaughter, processing, handling and storage due to poor hygiene and inadequate staff training.
It is not unusual, for instance, to see butchery attendants handling money and meat at the same time in Kenya. There is no hand-washing between handling money and the meat.
It is also common to find flies crawling on meat in butcheries.
The danger meat poses to humans can be minimised through diligent measures by responsible government agencies and other players in the value chain.
Good sanitation and hygiene have been shown to be the most effective tools of ensuring meat is not contaminated with bacteria and other micro-organisms.
On the other hand, disease prevention such as vaccination, good nutrition and management of livestock, coupled with appropriate use of antimicrobial drugs have been shown to be highly effective in preventing the development of antimicrobial resistance.