Principle Microbiology

Mary Mallon (September 23, 1869 – November 11, 1938), also known as Typhoid Mary, was the first person in the United States to be identified as a healthy carrier of typhoid fever. Over the course of her career as a cook, she is known to have infected 53 people, three of whom died from the disease. Her notoriety is in part due to her vehement denial of her own role in spreading the disease, together with her refusal to cease working as a cook. She was forcibly quarantined twice by public health authorities and died in quarantine. It is possible that she was born with the disease, as her mother had typhoid fever during her pregnancy.

Mallon was born in 1869 in County Tyrone, Northern Ireland, and emigrated to the United States in 1884. She worked as a cook in the New York City area between 1900 and 1907. She had been working in a house in Mamaroneck, New York for less than two weeks when the residents came down with typhoid. She moved to Manhattan in 1901 and members of the family for whom she worked developed fevers and diarrhea and the laundress died. She then went to work for a lawyer until seven of the eight household members developed typhoid. Mary spent months helping to care for the people she made sick, but her care further spread the disease through the household. In 1906, she took a position in Long Island. Within two weeks, six out of eleven family members were hospitalized with typhoid. She changed employment again and three more households were infected.

People catch typhoid fever after ingesting food or water which has been contaminated during handling by a human carrier. The human carrier is usually a healthy person who has survived a previous episode of typhoid fever but in whom the typhoid bacteria have been able to survive without causing further symptoms. Carriers continue to excrete the bacteria in their feces and urine. It takes vigorous scrubbing and thorough disinfection with soap and hot water to remove the bacteria from the hands. When typhoid researcher George Soper approached Mallon with the news she was possibly spreading typhoid, she adamantly rejected his request for urine and stool samples to ascertain whether she was a typhoid carrier. Soper left and later published his findings in the June 15, 1906 issue of the Journal of the American Medical Association.[1] On his next contact with her, he brought a doctor with him, but was again turned away. Mallon's denials that she was a carrier were based in part on the diagnosis of a reputable chemist who had found she was not harboring the bacteria. It is possible she was in temporary remission when tested. Moreover, when Soper first told her she was a carrier, the concept that a person could spread disease and remain healthy was not well known. During a later encounter in the hospital, he told Mary he would write a book about her and give her all the royalties; she angrily rejected his proposal and locked herself in the lavatory until he left.

Swine influenza (also called swine flu, hog flu and pig flu) refers to influenza caused by those strains of influenza virus, called swine influenza virus (SIV), that usually infect (is endemic in) pigs. As of 2009 these strains are all found in Influenza C virus and the subtypes of Influenza A virus known as H1N1, H1N2, H3N1, H3N2, and H2N3. Swine influenza is common in pigs in the midwestern United States (and occasionally in other states), Mexico, Canada, South America, Europe (including the United Kingdom, Sweden, and Italy), Kenya, Mainland China, Taiwan, Japan and other parts of eastern Asia. Transmission of swine influenza virus from pigs to humans is not common and does not always cause human influenza, often only resulting in the production of antibodies in the blood. The meat of the animal poses no risk of transmitting the virus when properly cooked. If transmission does cause human influenza, it is called zoonotic swine flu. People who work with pigs, especially people with intense exposures, are at increased risk of catching swine flu. In the mid-20th century, identification of influenza subtypes became possible, this allows accurate diagnosis of transmission to humans. Since then, fifty confirmed transmissions have been recorded, Rarely, these strains of swine flu can pass from human to human. In humans, the symptoms of swine flu are similar to those of influenza and of influenza-like illness in general, namely chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort. The 2009 flu outbreak in humans, known as "swine flu", is due to a new strain of influenza A virus subtype H1N1 that contains genes closely related to swine influenza. The origin of this new strain is unknown. However, the World Organization for Animal Health (OIE) reports that this strain has not been isolated in pigs. This strain can be transmitted from human to human, and causes the normal symptoms of influenza. Pigs can become infected with human influenza, and this appears to have happened during the 1918 flu pandemic and the 2009 flu outbreak.

The main raw materials used in beer production are as follows...


Malt
Malt adjuncts
Hops
Water

Malt :- The malt is prepared from carefully selected barley. This barley is first cleaned and then steeped in water for period up to two days. The excess water is then drained and the soaked barley is further incubated for periods of approximately four to six days to allow formation of a short rootlet and acrospire. This germination step allows the formation of highly viscous α - amylase, β - amylase and proteolytic enzymes, as well as flavor and color components.

At the end of incubation, the temperature is just raised to stop the germintaion without harming any enzyme, although high temperatures can be employed to obtain dark colored stout and bock beer fermentation.

Hence the green malt produced is carefully dried and stored. The preparation of good malt is an exacting task and it requires careful selection of barley and close supervision of malting process.
So most of the beer producing companies do not produce their own malt. But they rely on other companies who specialize in this art.

The other raw materials needed in beer production well be described soon.