• second world war an outbreak from Salmonella were traced from imported spray dried and bulk liquid egg
• they multiplied during preparation and storage
• pasteurization by the Liquid Egg Regulations 1963 has made the product relatively save

1. Most recent, outbreaks occur in egg-related products such as mayonnaise, cold desserts and ice cream. 
2. Salmonella multiply without cooking after addition of raw egg.
3. Bacteria from the egg shell multiply in huge numbers during storage for 1 to 2 days at warm room temperature.
4. Generation time of 80 min at 20°C, one bacterium can become a billion (10^9) in 40 h, and with a generation time of 40 min at 25°C, it can do so in 20 h. 
5. Safe food now is due to smaller bacterial numbers, lower than human oral infective dose. In order for Salmonellosis to occur, the dosage of bacterial numbers must be sufficiently large enough to infect by ingestion through mouth.
6. In study,  eggs at 35°C were immersed in a cold suspension of S. montevideo, S. oranienburg or S. typhimurium bacteria and sampled after drying and storage at 29°C for periods of up to 29 days.
7. Immediately after inoculation, Salmonella was absent from the yolk and albumen.
8. They penetrated in small numbers into some eggs during the first week, but penetrated into and multiplied to large numbers ( 107-109/ml) in most eggs during the third and fourth weeks. The egg’s defences were therefore highly effective in the first fortnight of storage at 29°C, but later broke down.
9. Eggs laid on damp, faeces-soiled earth will draw in not only Salmonella, but also numerous putrefactive faecal bacteria such as Pseudomonas and gram negative anaerobes. Some of these saprophytes will multiply faster than Salmonella at ambient temperatures and probably make the egg inedible before its salmonella content is large 

1. Contaminated from breeder flocks, hatchery environment, feed and litter as well as water troughs in the pens 
2. Until 1988, poultry meat was considered the major source of outbreak Salmonella-food poisoning in Britain
3. Arumugaswamy et al. (1995) reported 39.4% chicken portions, 35.3% chicken liver and 44.4% chicken gizzard were contaminated with Salmonella spp. in Malaysia.

•  Adore moist environment shielded from the sun
• b. Have the ability to survive between the pH of 4 and 8+.
• c. Facultative anaerobes which can adapt under low oxygen environment conditions. 
• d. They also can grow between 8 degrees Celsius and 45 degrees Celsius. 

• The increased use of surface water for supply and irrigation lead to potential threat to the human health. 
• When rainfall is present, the population of salmonella increases. 
• Due to it being a facultative anaerobe, they are also found in manure and human sewage which could cause water contamination. 
• Has been uncovered that the water used for irrigating crops may harbor Salmonella. 

• Salmonella encounters the acidic nature of the stomach and this will trigger its acidic tolerance survival response. 
• They travel through the mucous layer by invading intestinal epithelial cells, M-cells and dendritic cells. 
• Salmonella has genes that encode for type 3 secretion system (T3SS) which are located on Salmonella pathogenicity island 1 (SPI-1).
• Invade by creating membrane ruffles around itself which enables endocytosis.
•  M-cells transport Salmonella across the epithelial boundary to the dendritic cells.
• Spreads systematically by utilizing the dendritic cells.
• Another way of infection is by Salmonella being taken up by CD-18 expressing phagocytes
• These phagocytes that contain Salmonella travel across the tissue barriers and acts as a transportation for Salmonella from the lumen of the gastrointestinal (GI) tract to the systemic circulation. 
• Salmonella are also know to disturb tight junctions located between epithelial cells which functions to prevent leakage of water, ions, nutrients and immune cells from leaking into the GI tracts. 

• Salmonella taken up by the intestinal macrophages.
• The SPI-2 T3SS modify the phagosome into a salmonella containing vacoule (SVC) and revamps the host cell to make it more conducive for the survival and replication of the Salmonella. 

-What is raw milk?

• Raw milk is milk from cows, goats, sheep, or other animals that has not been pasteurized.

• A wide variety of germs that are sometimes found in raw milk, can make people sick, including bacteria (e.g., Brucella, Campylobacter, Listeria, Mycobacterium bovis (a cause of tuberculosis),Salmonella, Shiga toxin-producing Escherichia coli [e.g., E. coli O157], Shigella, Yersinia), parasites (e.g., Giardia), and viruses (e.g., norovirus).

• Pasteurization is the process of heating milk to a high enough temperature for a long enough time to kill illness-causing bacteria contained in the milk. As most commonly applied, pasteurization heats milk to a high temperature for a short time, which kills the bacteria that cause illness. It was invented in a time when millions of people became sick and died of diseases like tuberculosis, scarlet fever, typhoid fever, and other infections that were transmitted through raw milk. Pasteurization has prevented millions of people from becoming ill.
• Routine pasteurization of milk began in the United States in the 1920s and became widespread by 1950 as a means to reduce contamination and reduce human illnesses. It led to dramatic reductions in the number of people getting sick from diseases that had previously been transmitted commonly by milk. Most public health professionals and health care providers consider pasteurization to be one of public health’s most effective food safety interventions ever.
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Bacteriological quality and safety of raw milk in Malaysia

• Salmonella is found in domestic and wild animals, including poultry, wild birds, swine, cattle, and rodents. Reptiles such as iguanas, bearded dragons, turtles, and domestic pets such as chicks, dogs and cats may harbour the bacteria. Humans are carriers of certain types of salmonella.
• Salmonella can pass through the entire food chain from animal feed, primary production, and all the way to households or food-service establishments and institutions.
• Salmonellosis in humans is generally contracted through the consumption of contaminated food of animal origin (mainly eggs, meat, poultry, and milk), although other foods, including green vegetables contaminated by manure, have been implicated in its transmission.
• Person-to-person transmission can also occur through the faecal-oral route.
• Human cases also occur where individuals have contact with infected animals, including pets. These infected animals often do not show signs of disease.

• fertilized with contaminated manure.
• irrigated with contaminated water.
• in contact with contaminated products during cutting, washing, packing and preparation processes. 

a) Tomatoes

-Tomatoes have smooth surface but even so, their surfaces do contain tiny pores that make homes for bacteria.

• In the US, FDA estimates 383 current Salmonella cases linked to contaminated tomatoes across 30 states, including Washington, D.C., since April 10 when the earliest known victim is reported. The outbreak is blamed on Salmonella serotype Saintpaul, an uncommon type of Salmonella, which are bacteria that can live in the intestinal tracts of humans and other animals (Bryner, 2012). 

•  In 2007 a Salmonella outbreak in the UK was traced back to imported basil. 
• Between 1996 – 2000, 23% of the UK's infectious intestinal disease outbreaks like Salmonella is caused by contaminated food, and of these, 4% were linked to prepared salad.
• In 2016, Australian health officials issued a national recall of packaged lettuce and other salad products after 28 cases of Salmonella poisoning in the state of Victoria.

• Pet store owners, veterinarians, and pediatricians should provide information to owners and potential purchasers of reptiles about the risk for acquiring salmonellosis from reptiles.
• Persons should always wash their hands thoroughly with soap and water after handling reptiles or reptile cages.
• Persons at increased risk for infection or serious complications of salmonellosis (e.g., children aged less than 5 years and immunocompromised persons) should avoid contact with reptiles.
• Pet reptiles should be kept out of households where children aged less than 5 years or immunocompromised persons live. Families expecting a new child should remove the pet reptile from the home before the infant arrives.
• Pet reptiles should not be kept in child care centers.
• Pet reptiles should not be allowed to roam freely throughout the home or living area.
• Pet reptiles should be kept out of kitchens and other food-preparation areas to prevent contamination. Kitchen sinks should not be used to bathe reptiles or to wash their dishes, cages, or aquariums. If bathtubs are used for these purposes, they should be cleaned thoroughly and disinfected with bleach.

• Cook poultry, ground beef, and eggs thoroughly. Do not eat or drink foods containing raw eggs, or raw (unpasteurized) milk.
• If you are served undercooked meat, poultry or eggs in a restaurant, don't hesitate to send it back to the kitchen for further cooking.
• Wash hands, kitchen work surfaces, and utensils with soap and water immediately after they have been in contact with raw meat or poultry.
• Be particularly careful with foods prepared for infants, the elderly, and the immunocompromised.
• Wash hands with soap after handling reptiles, birds, or baby chicks, and after contact with pet feces.
• Avoid direct or even indirect contact between reptiles (turtles, iguanas, other lizards, snakes) and infants or immunocompromised persons.
• Don't work with raw poultry or meat, and an infant (e.g., feed, change diaper) at the same time.
• Mother's milk is the safest food for young infants. Breastfeeding prevents salmonellosis and many other health problems.

Salmonella in dry foods

• A comprehensive, validated, thermal reduction process for the raw materials.
• A knowledge of how Salmonella survives in the processing environment and how it can be controlled.
• The use of decontamination techniques as a final process step that could reduce the risk of Salmonella present as a result of cross-contamination from the process environment.

1. With a sterilized straight inoculation needle touch the top of a well-isolated colony
2. Inoculate TSI Agar by first stabbing through the center of the medium to the bottom of the tube and then streaking on the surface of the agar slant. 
3. Leave the cap on loosely and incubate the tube at 35°C in ambient air for 18 to 24 hours.

• Iron content

• Fat content

• Plants

• Eggs