Nov 02 - 08, 2009

Do you think that all bacteria are bad? Bacteria are not always bad. There are actually some beneficial bacteria, which help us. It is true. In the beginning of the 20th century, a Russian Nobel laureate called Eli Metchnikoff discovered some strains of bacteria inside human bodies and which are good bacteria.

These good bacteria are called 'probiotics' and there are those bacteria which help the function of these probiotics.

The human body is home to millions of beneficial bacteria. We house millions of bacteria on our skin and in our nose, mouth, and gut.

- Up to 500 species can be found as normal oral flora

- There can easily be 25 species living in a single mouth

- A milliliter of saliva can contain as many as 40 million (4 x 107) bacterial cells

- 108 bacterial cells present in the cecum (the initial part of the colon) per milliliter of content is normal and many of these species are different from those found in the mouth

Our gastrointestinal tract provides residence to both beneficial and potentially pathogenic microorganisms. Fully 10 percent of the dry weight of a human consists of bacteria. The bacteria act to break down foodstuffs, and so directly participate in the digestive process.

As well, some of the intestinal bacteria produce products that are crucial to the health of the host. For example, in humans some of the gut bacteria manufacture vitamin K, vitamin B12, biotin, and riboflavin. These vitamins are important to the host but are not made by the host. The bacteria benefit by inhabiting an extremely hospitable environment. The natural activities and numbers of the bacteria also serve to protect the host from colonization by disease-causing microorganisms. The importance of this type of symbiosis is exemplified by the adverse health effects to the host that can occur when the symbiotic balance is disturbed by antibiotic therapy.

The human body has different means of fighting with infections. It fights through the layer of skin, through the lining of mucous, through the immune system and finally through gut microflora. These gut microflora are nothing but the helpful bacteria, and they are present in the intestines. The common gut microflora present inside the human body are lactobacilli, bifidobacteria, eubacteria, clostridium, bacteroides, and the spifida bacteria.

These beneficial bacteria are even found in foods such as buttermilk, yoghurt, sour cream, and even some frozen desserts. These lactic acid bacteria are able to convert sugars and carbohydrates into lactic acid. Thus, this process creates the fermented taste but it also lowers the pH and reduces the risk of other organisms growing in the food product. This in turn can cause huge benefits for people who want to prevent gastrointestinal infections.

Oral ingestion of probiotics has shown a marked improvement in Humans Different studies have shown that the ingestion of probiotics have shown a marked improvement in people who are lactose intolerant, and other diseases such as diarrhea, gastrointestinal infections, and even vaginal candida or yeast infections. Helpful bacteria have also been of great help in the cases of irritable bowel syndrome, colitis, lowering blood pressure, lowering cholesterol, and even in improving the absorption of minerals in the body.

Unfortunately these gut microflora which are normally present within the intestines are destroyed by a wide variety of factors, such as stress, alcohol, diseases, antibiotics and certain drugs, and even exposure to toxic substances. These beneficial bacteria are destroyed in these conditions, which allow the other harmful bacteria to thrive, causing health problems.

Helpful bacteria are also available now a day in the form of tablets and capsules. However, it is best advised by various doctors to take these bacteria in the natural form as well. As mentioned before, these beneficial bacteria are found in foods such as yoghurt, buttermilk, sauerkraut, tempeh, kefir, kim chi, miso, and such other fermented foods. You can even take different prebiotics to help the functioning of these probiotics. These are found in foods such as oatmeal, barley, flax, onions, green vegetables, berries, bananas, legumes, and whole grains.

The best-known example is the consumption of yogurt and other fermented milk products, which have the combined effect of reducing spoilage, and enhancing tolerance for partially lactose-intolerant individuals.

A major industry has developed to produce bacterial preparations, in the form of powders, drinks, and dairy products, all sold as healthy and beneficial (and sometimes tasty) supplements. Although some of their promises are unrealistic (some products do not even contain viable bacteria), it is generally accepted that certain bacteria are beneficial, especially when intestinal flora is unbalanced (as with antibiotic-associated diarrhea).

The most commonly used bacterial species are lactobacilli and bifidobacterium.


These beneficial bacteria comprise of different species of bacteria namely the lactobacilla, eubacteria, clostridium, bacteroides and the spifida bacteria. These are said to enter the human body since birth. As a newborn baby is born, bacteria present at the mother's vagina are directly transferred to it. With the settling in the intestines, for a girl child, these bacteria move to the vaginal area and are said to do well in areas that are moist in nature and contain warmth.

While residing here, the bacteria do whatever is necessary to prevent the entrance of other pathogenic bacteria into the body through this route.

As the baby grows up into becoming an adult, these beneficial bacteria intestine undertakes many activities and one of them is to repeatedly break down different starch molecules and long chains of carbohydrates that are brought into the small intestines from the large intestines. This action ensures that shorter chained fatty acids, body energy, and other helpful material that might be used in the growth process by the person are achieved.

Another activity done by these beneficial bacteria intestine is the suppression of the growth of bacteria that are considered to be harmful to the human body. By residing in the intestines, these beneficial bacteria act as our security guards and colonize the whole territory. Indeed when they suspect that there has been an invasion of pathogenic kind of bacteria, the beneficial bacteria move quickly to curb the situation by producing strains that would make it impossible for the hazardous bacteria to survive or improve the immune system of the host organism so that it is strong enough to destroy these foreign invaders.

Beneficial bacteria intestine improve the protective barrier of the digestive tract. This is one of the ways the bacteria ensures that ingested food is let to flow down to the stomach without it being subjected to any constraints put across by any other harmful bacteria. When food is left to flow down the digestive tract without any hindrance, chances are that it will undergo a proper digestion and this way food metabolism rate improves. All necessary nutrients are therefore absorbed easily and the person becomes the overall beneficiary.

However, to sustain these beneficial bacteria intestine so that they continue helping you in life, food rich in fiber material is required. This fiber content could be obtained from green leafy vegetables, leguminous products, and grains. The fiber in these food staffs is believed to provide the helpful bacteria in the intestines with proper nutrients that help them to successfully undertake their duties.

Unauthorized antibiotic intake may on the other hand reduce the number of these beneficial bacteria. Antibiotics are said to tamper with the formation of the outer cover of the cell structure of the bacteria. This cell cover is the one, which engulfs all the contents of the bacteria and with it destroyed; it would mean that the beneficial bacteria gets to die.


A number of bacterial species are required for the preparation of food, and may or may not arrive on our plate alive. Notably, many cheese varieties are dependent on their characteristic bacterial starter culture. Fermenting bacteria are required to produce sausages and sauerkraut; they even help cacao and coffee beans to attain their desired flavor.

Beneficial bacteria have also found their uses in other places. In today's world, the environment and its related issues are steadily gaining a lot of importance. It has been seen that helpful bacteria are useful in dissolving organic sludge from water, breaking down the growth of algae, reducing the various noxious odors such as hydrogen sulfide odors, reducing ammonia levels, promoting faster growth of fish in the water body, and also defeating unhealthy bacterial growth in the water body.

Microbial symbiosis has been a survival feature of bacteria since their origin. There are several well-known examples of bacterial mutualism one of them is the symbiotic mutualism which is the colonization of the nodules of leguminous plants by bacteria of the genus Rhizobium. The bacteria convert free nitrogen gas into a form of nitrogen called nitrate. This form of nitrogen can be readily utilized by the plant, which cannot otherwise use the gaseous form of nitrogen. The plant benefits by acquiring a readily available nitrogen source, and, as for the intestinal bacteria, Rhizobium benefits by virtue of the hospitable environment for growth.

Microbial symbiosis can be exquisite. An example is the Gram-negative bacterium Xenorhabdus nematophilus. This bacterium lives in a nematode called Steinernema carpocapsae. Both organisms require the other for survival. Thus, the symbiosis is obligatory. The bacterium in fact supplies toxins that are used to kill insect that the nematode infects.

The scope of microbial symbiosis in nature is vast. Numerous other examples of microbial symbiosis exist in nature. Animals, plants as exotic as coral, insects, fish, and birds all harbor microorganisms that assist them in their survival. Indeed, the ancient roots of microbial symbiosis may be indicative of a more cooperative evolution of life on earth than prior studies indicated.

These facts are truly impressive for organisms so small that they are invisible to the eye. It is to our advantage to look at bacteria as more than just pathogens.



On World Pneumonia Day 2009, a leading international infectious disease expert has highlighted the importance of pneumococcal disease vaccination in preventing secondary pneumococcal infections which can cause severe illness like pneumonia and deaths associated with pandemic influenza.

The United Nations estimates that 98 children die every hour in the Asia Pacific region due to pneumonia. In addition, 49 children die every hour in the Asia Pacific due to pneumococcal pneumonia.

According to Keith P. Klugman, Professor of Global Health, Rollins School of Public Health and Professor of Medicine for the Division of Infectious Diseases, School of Medicine Emory University in Atlanta, pneumococcal disease is the leading cause of pneumonia in children and vaccination is the most effective way to ensure children are protected.

Although pandemic flu has the potential to cause death on its own, children who contract the illness are vulnerable to secondary infections from bacterial pathogens including pneumococcus, which may lead to pneumonia, which is more serious than the primary flu infection itself.

Pneumococcal vaccines may reduce the mortality and morbidity associated with viral respiratory infections including pandemic influenza by reducing secondary infections leading to pneumonia, and should be considered as an essential part of pandemic flu planning.

"In countries where there has been a broad uptake of the 7-valent pneumococcal vaccine, rates of pneumococcal related illnesses have significantly reduced. However, vaccination rates in Asia remain low," said Professor Klugman.

"We therefore expect to see illness and death due to influenza-related pneumococcal disease in Asia, unless pneumococcal vaccination rates increase," Professor Klugman said.

Pneumococcal disease is the leading cause of vaccine preventable death in the world. Half of the top 10 countries with the highest prevalence of pneumococcal disease are found in Asia. The disease is the leading cause of pneumonia in children.

The 7-valent pneumococcal conjugate vaccine (PCV7) has been widely used globally for nine years and is the current gold standard in pneumococcal disease prevention. Based on its efficacy in reducing the incidence of invasive pneumococcal disease in infants 7, the World Health Organization (WHO) recommended for the priority inclusion of PCV7 in national childhood immunizations worldwide since 2007.

PCV7 is widely available throughout Asia from doctors. It is currently included on the national childhood immunization program (NIP) in Hong Kong and Macau and will soon be available on the NIP in Singapore.

"For countries that do not have the pneumococcal conjugate vaccine available as part of their national immunization program, the clear link between pandemic influenza and associated rates of preventable death and illness, provides an important reason to have it included," Professor Klugman said.


In clinical studies (n=18,168), the most frequently reported adverse events included injection site reactions, fever (?38∞C/100.4∞F), irritability, drowsiness, restless sleep, decreased appetite, vomiting, diarrhea, and rash. Risks are associated with all vaccines, including PCV7. Hypersensitivity to any vaccine component, including diphtheria toxoid, is a contraindication to its use. PCV7 does not provide 100% protection against vaccine serotypes or protect against non-vaccine serotypes. The decision to administer PCV7 should be based on its efficacy in preventing invasive pneumococcal disease (IPD).


Pneumococcal disease is complex and describes a group of illnesses all caused by the bacterium Streptococcus pneumoniae. Pneumococcal disease affects both children and adults, and includes invasive infections such as bacteraemia/sepsis and meningitis, as well as pneumonia and otitis media (middle ear infection).