Entamoeba histolytica can cause dysentery

Currently five types of protozoa are of concern: Entamoeba histolytica, Giardia lamblia, Cryptosporidium parvum, Naegleria and Acanthamoeba. Entamoeba histolytica is a microscopic endoparasitic of humans. It is chiefly found in the colon of large intestine.

Entamoeba histolytica, the cause of amoebic dysentery, is spread principally by fecal contamination of water, food, body parts and diverse objects: sexual partners make an epidemiological impact.

It can be transmitted by the poor personal hygiene of food handlers, contamination of ready-to-eat foods such as fruits or vegetables, from drinking water, and by insect vectors such as flies.

Entamoeba histolytica infection is widespread in subtopic areas. Infection begins when trophozoites of Entamoeba histolytica invade the colonic mucosa.

The majority of infected people do not display any pathology, and the parasite exists as a commensal, continuing to multiply and spread. Only a small fraction of the infected individuals show overt symptoms of amebiasis with invasion in the intestinal tissues or in some extraintestinal sites, such as liver.
Entamoeba histolytica can cause dysentery

Foods that could be contaminated with Staphylococcus aureus

Staphylococcus aureus a Gram-positive bacterium produces enterotoxins, which are causative agents foodborne intoxication. Almost any food (except acid product) is suitable for the growth of Staphylococcus aureus, but certain foods have been most often the cause of staphylococcal poisoning.

Consumption of foods contaminated with staphylococcus aureus enterotoxins results in the onset of acute gastroenteritis within 2-6 h.

The food types most frequently involved in this disease are ham and ham products, bakery goods with egg custard filling, chicken products and especially chicken salad, potato salad and cheddar cheese. Others are shrimps, low acid foods stored and served between 5 ° C and 55 ° C.

The reason why ham products are frequently involved is that in their preparation they may contaminated with Staphylococcus aureus, and since this product contains 2-3% salt, other bacteria might grow and inhibit the growth of staphylococci are themselves inhibited by the salt.

Also people handle ham and its products are apt to believe that such foods are not perishable. However, ham and ham product are perishable and should always be held at 4.4 ° C or below.

It is generally understood and accepted that Staphylococcus aureus as a food intoxicant presents a risk only when the growth to high numbers occurs.

Since Staphylococcus aureus cannot grow at temperature below 7° C and that multiplication of Staphylococcus aureus in raw products is inhibited or slowed down by competing accompanying microflora, those high numbers are normally not reached under the condition of maintained cold chain.

To reduce Staphylococcus aureus food poisoning, the amount of manual handling should be minimizes. Slicers should be dismantled when cleaned and sanitized. Ham should be sliced when it its cold. Rapid cooking should be permitted by storing food in small, loosely covered containers.
Foods that could be contaminated with Staphylococcus aureus

Raw milk associated with Campylobacter jejuni

Raw milk is a common source of infections. The bacterial are often carried by healthy cattle and by flies on farms. Non-chlorinated water may also be a source of infections. However, properly cooking chicken, pasteurising milk, and chlorinating drinking water will kill the bacteria.

Raw milk may become contaminated with C. jejuni in one of two ways. It may excreted directly by a mastitis udder or feces may contaminated the product.

Contamination of milk from C. jejuni mastitis is thought to be rare, but direct milk excretion leading to human cases has been reported.

Milkborne campylobacteriossis outbreaks have even almost invariably associated with consumption of raw or inadequately pasteurised cow’s milk.

However, a few cases of C. jejuni and E. coli enteritis have been trace to ingestion of raw goats milk in United States, Great Britain and Australia, with the epidemic strain identified in fecal samples from incriminated goats.
Raw milk associated with Campylobacter jejuni

Food commonly associated with salmonellosis

Salmonellosis is a bacteria disease characterized by sudden onset of headache, abdominal gain, diarrhea, nausea, sometimes vomiting and almost always fever. Food-associated Salmonella infections in the United States are estimated by the US Department of Agriculture to cost $3 billion annually.

Shellfish, egg products, prepared salads, and to some extent, raw and cooked meats have often associated with the transmission of salmonellosis.

Salmonella enteritidis outbreaks are most frequently associated with the consumption of poultry products especially undercooked eggs and chicken.

Raw shellfish may be taken from waters contaminated with Salmonella bacteria and cooked shellfish meats may contaminated with humans since they are usually removed from their shell by hand.

Poultry of all types, beef cattle, and hogs may have salmonellosis or be carriers of the organisms causing the disease; hence under conditions of cooking in which these organisms are not destroyed, they may be transmitted by humans.  

Latest large outbreaks have been linked with eating tomatoes, jalapeno peppers, and peanut butter.

From 1998 through 2003, the US Department of Agriculture-Food Safety Inspection Service reported isolation of Salmonella from 11.2% to 22.5% of broiler and ground chicken samples, respectively.

As it is impossible for many raw foods to be produced free from Salmonella at source, it is important to establish animal husbandry and crop agriculture regimes that can make a positive contribution to minimizing the frequency and level of contamination of these primary raw materials by Salmonella.
Food commonly associated with salmonellosis 

Food contamination by bacteria

Most of the bacteria are transmitted via food and water as a result of contamination with feces.

The main bacteria that cause food infections via colonization in the intestinal via colonization in the intestinal tract are Salmonella, Listeria monocytogenes, Yersinia enterocolitica and Shigella.

None of the bacteria can multiply in food or water or indeed outside the body of the host in which they developed. If they occur in food or water, one hopes that they will be inactivated or killed before they can infect a consumer or the vehicle.

There are a number of reasons and sources which result in the prevalence of bacterial contamination in food products, such as:
*Premises which are difficult to clean
*Lack of staff discipline
*Incorrect staff and product flow
*Poor air quality
*Incorrect direction of air movement

Food that is cooked and then not contaminated before being served is unlikely to serve as a vehicle for most of the bacteria.

Salmonella is the second most common cause of illness traced to contaminated foods and water. Foods most susceptible to Salmonella contamination are meat, fish, poultry, eggs and dairy products.

Much of the bacterial contamination of foods in restaurants, commissary kitchens and commercial processors are due to the poor personal hygiene of workers. Failure to wash hands after using the bathroom, sneezing and coughing into food, and picking noses and skin blemishes can all transmit pathogenic bacteria to food.
Food contamination by bacteria 

Staphylococcus aureus bacteria

The bacterium that causes staphylococcus poisoning is Staphylococcus aureus, the same bacterium that causes white-head pimples, infections, boils, and carbuncles.

Staphylococcus aureus is one of the most dangerous types of bacteria because of the many serious infections it can cause and because of the difficulty in treating these infections.

These cells are spherical or ovoid in shape, non-motile and liquid cultures, arrange themselves in grapelike clusters, in small groups, in pairs or in short chains.

They grow best in the presence of air (oxygen) but they also grow in the absence of air. They will grow in media or in foods that contain as much as 10% salt (NaCl). When this organism grows in foods they produce a toxin that can be filtered away from foods and the bacterial cells.

There are three major contamination scenarios existing:
* Staphylococcus aureus frequently associated with dairy cows and is leading cause of intramammary infection

*The second major source is recontamination by food handlers carrying enterotoxin-producing Staphylococcus aureus in their noses or on their hands

*Air, dust and biofilm in difficult-to-access niches in primary and secondary food production facilities can also serve as source of Staphylococcus aureus to foods.

The toxin is not destroyed by cooking. Every year in the United States, roughly 400,000 hospital patients are infected by Staphylococcus aureus.

Symptoms include vomiting and diarrhea that occur shortly after ingestion of Staphylococcus aureus toxin-contaminated food.
Staphylococcus aureus bacteria