How to quit smoking

Smoking affects almost all organs of our body, rarely an organ is spared where smoking isa not a predisposing factor for causing cancer. Apart from cancer it can cause impotency, sterlity and even loss of vision.

Why do we smoke

Now a days people are leading a stressful life. In order to struggle for existence everyone are just inviting all sort of stress which lead to depression and a false belief that smoking can reduce stress, we get addicted to this deadly habit.

Gradually our body gets habituated to the nicotine and then without them we feel more depressed and sometimes gets agitated.

It is not easy to quit smoking as I have read somewhere who said "It is easy to quit smoking and I have done it several times". It clearly indicates that it is difficult to say no to smoking permanently. A strong determination, will power is required.

Some yoga and pranayama is advisable to tackle with mental stress you face while you are in the abstinence period. Here are some yoga and pranayama which can provide you a mental peace and a good fealing even when you are in real urge of having a puff.

Be regular here and follow the yoga and pranayama. Mind, body, spirit and you.

Nicotine patch to quit smoking

Every one dont have that strong will power to quit smoking, they really need something alternative which reduces the urge to smoke. Nicotine patch has been the answer for them. According to research the success rate of nicotine patch has been seen almost about 200%. Research was made at Duke University Medical Center.

According to Jed Rose Jed Rose, PhD, director of the Duke Center for Nicotine and Smoking Research and lead author of the paper that is published online in the current issue of the journal Nicotine and Tobacco Research nicotine patch is only recommended for use after the quit date.

There was a worry of overdose of nicotine who are using nicotine patch as well as smoking intermittently, however research proved that concurrent use of nicotine patch along with smoking are safe.

During the research made by Jed Rose,he observed that the smoking significantly reduced who started using nicotine patch and the withdrawl symptoms was also very negligible, which reduces the incidence or reinstating the habit of smoking.

Nicotine patches are available at most places, though research are still going on but the use of nicotine patch is on. Rose believes similar pre-cessation intervention may work for other drugs used for smoking cessation, but more research is needed to support that hypothesis.


The patch is generally used at left index finger, from where it is gradually absorbed and the urge of smoking is reduced accordingly, now a days nicotine containg chewing gum is also available in market.

In spite of all these thing a self determination and strong will power hold the key to quit smoking.

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Traveller,s vaccine : Yellow fever vaccine

If you have ever travelled abroad in some countries which are endemic or hyperendemic, you might have taken a vaccine for yellow fever. Though the disease does not exist in India but the Indian climate is optimum for a yellow fever virus to grow, the vector for this Aedes aegypti mosquito is also in abundance in India, but what is absent is the virus itself. Thus once the virus gets entry in the country it can spread the disease like a fire. So extreme caution is taken to stop the virus and all person are vaccinated when they travel abroad especially in countries of African sub continents.

Currently available yellow virus vaccine

Yellow fever vaccine is a live attenuated virus preparation made from 17D yellow fever virus strain. This vaccine virus family is the foundation for the 2 currently available vaccine type, 17D - 204 lineage and 17D D lineage. The former is used both in USA and Australia and the later is used in Brazil.

Use of yellow fever vaccine

It may be a question that when the disease yellow fever does not exist in India then what is the use of yellow fever vaccine. The answer is that the person travelling abroad if not vaccinated may carry the virus and the disease may occur. Thus children aged 9 month or more and all adults travelling to or living in areas of South Africa, Africa where the yellow fever vaccination is officially reported should be vaccinated.

Vaccination is also recommended for travellers to countries that do not officially report the disease but that lie in the yellow fever endemic zone.

Why infants below 9 months of age should not be vaccinated for yellow fever

Calculation of age specific rate of yellow fever vaccine associated encephalitis is impossible as age specific vaccination records are not available. Several reports show higher incidence of encephalitis below 9 months of age and the vaccine contains live virus so the FDA and the manufacturer recommends that vaccination for yellow fever of infants below 9 months should be avoided.

Last but not the least for Indian population it is recommended as stated earlier that all permanent Indian resident should take yellow fever vaccine while travelling to countries where yellow fever is endemic or hyperendemic.

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Malaria vaccine : Blocking transmission of Malaria

Malaria has been epidemic, not only in India but in many countries like China, Indonesia etc. The discovery of chloroquine was a revolution in treating malaria, but gradually resistant cases started emerging and now more than 20% of cases are chloroquine resistant malaria.

As the vector for malaria, the female anopheles mosquito reside at clean and stored water, it was very difficult to prevent malaria merely by maintaining hygiene. This lead to the need of something which can block the spread or transmission of malaria, and this need forced scientists to work on malaria vaccine.

Possible targets of malaria vaccine development

In human beings the asexual cycle of malarial parasites occurs while in mosquitoes the sexual cycle occurs, this makes the possible target in blocking transmission of malaria or malaria vaccines as

Pre erythrocytic malaria vaccine

The preerythrocytic malarial vaccine can prevent
i. Sporozoites inoculated by the infected mosquito during the blood meal before they invade the liver cells.

ii. Sporozoites multiplying within the liver cells to give rise to merozoites.

Blood stage malaria vaccine

i. Inside the red cells merozoites transform into trophozoites, grow and then divide finally to give dozens of merozoites, which reinvade the new red cells after bursting of the infected cells. These merozoites can be the vaccine target.

ii. During intracellular growth of the parasites they express some antigens on the surface of red cells which may be the vaccine target.

Transmission blocking malaria vaccine

Vaccines targeted against gametocyte or gametes are known as transmission blocking vaccines. Some trophozoites differentiate into sexual form, male and female gametocytes which mature to gametes in the digestive system of mosquito.

What are pre erythrocytic malaria vaccine

Pre-erythrocytic malarial vaccine have focussed largely on circumsporozoite protein which is the major surface protein of the sporozoites. The basic aim is to generate humoral immune response which will neutralize the sporozite and prevent it from invading the hepatocytes.

Once sporozoite reached the relatively immuno protected intracellular haven of a hepatocyte then cell mediated immunity is called upon to contain the infection.

A successful pre-erythrocytic vaccine will either kill the sporozoite before they invade hepatocytes or destroy it once they are inside the hepatocyte. This result in a disease preventing vaccine, an ideal vaccine, which will result in sterile immunity. Also it will be an ideal vaccine for the travellers as it would prevent clinical disease.

What are blood stage malaria vaccine

Blood stage malarial vaccine will either destroy the merozoites in the short time before they invade red cells or target malarial antigens expressed on red cell surface by invading parasites. Protection offered by these vaccines will be both antibody dependent and cell mediated immunity. These vaccines will suppress the exponential growth of dividing merozoites there by reducing the disease manifestation ie disease reduction vaccine. They will simulate natural immunity that is found in highly endemic zones.

What are transmission blocking malaria vaccine

Antibodies produced by these vaccines against gametocytes will be taken up by the mosquito during its blood meal along with the gametocytes. Within the mosquito the antigens become exposed to antibody thereby neutralizing the sexual stages.

These vaccines are termed altruistics, since they mediate their action within the mosquito and would protect not the vaccinee, but the next person beaten by that mosquito. Reduction in transmission rate could radically alter the incidence of the disease particularly in areas of low or moderate endemicity.

Chinese malarial vaccine

A China developed malaria vaccine is under trial in Shanghai, this is a move China hopes it will contribute to global prevention efforts of the deadly disease.

Seventy healthy volunteers will recieve the vaccine, code named PfCP2.9, at the Changhai hospital in shanghai, if the eight month trial is successful, full clinical trials will be conducted on adults and children where malaria is most prevalent.

The trials are funded by the worldwide non-profit fund PATH, and its malaria vaccine initiative. Shanghai based Wanxing Biological Pharmacy Co. Ltd. is also engaged in the research and development of the vaccine. The two organizations signed a agreement to carry out the clinical trials in Shanghai.

The trial will recieve 2 million US dollars from PATH which will also provide technical support and data analysis.

The PfCP2.9 malaria vaccine, developed by medical experts with the Shanghai No. 2 medical college of the Chinese people's Liberation Army (PLA), is one of 20 new malaria vaccine around the world which have recieved funding from PATH for clinical trials.

Numerous trials are also going on simultaneously and hundred vaccine development teams had applied for funding. We expect a full proof preventive vaccine very soon which will not only prevent from clinical disease but also prevent transmission.

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Development of HIV vaccines and its limitations

There has been numerous preventive programs, many programs by Government and even by NGO,s but inspite of these preventive programs, the HIV epidemics continues to spread throughout the world. WHO and UNAIDS estimated that at the end of 2008, the total number of people living with HIV/AIDS was approximately 75 millions. About 5 millions new cases are detected each year, thus it is clear that there is a desperate need for a preventive vaccine, but even a partially effective vaccine would have significant impact on the worldwide spread of the virus.

Target of HIV vaccine and its development

HIV subverts complement-mediated lysis in two ways :

1. It acquires the host membrane-bound complement control molecules DAF and CD 59 when it buds from host cells.

2. A site on the viral glycoprotein gp41 binds the soluble complement control molecule, factor H (CFH).

Based on these facts, they suggest that the factor H-biding site on HIV might be an appropriate site for directing protective abntibodies. The idea is to stimulate the formation of antibodies that have this site specificity. As a result, HIV will, theoritically not be able to down regulate complement and will be destroyed. This approach could possibly be augmented by antibodies which are specific to the DAF and CD59 molecules on the surface of the resistant HIV. However, it is not clear how such antibodies would avoid targeting host cells.

An advantage to this type of strategy is that protective antibodies could be use to passively immunize those already infected. As opposed to active immunization which stimulates an immune response.

The theory is backed up by some laboratory data. In one study, an antibody which neutralize a number of different lab stains of HIV-1 was found to bind to a site on gp41. This site was conserved in 72% of studied isolates an important copnsideration in the development of a vaccine to the highly variable HIV. Although this study did not target the CFH biding sites mentioned above, it does demonstrate the general feasibility of such an approach.

Limitations for developmet of HIV vaccine

The following are the hurdles the researchers are facig in the development of a vaccine against HIV.

i. Extreme genetic variability of the virus resulting from mutation and recombination.

ii. General lack of understanding of protective immunity against HIV.

iii. Absence of predictive animal models.

iv. Difficulties to implement clinical trials, especially in developing countries like India.

All of these factors impede progress in the search for an effective vaccine. HIV infects cells of the immune system, but can also be detected as free virus. It is therefor recognized that a vaccine should elicit both humoral immunity, which uses the antibodies, to fight the free virus, as well as cellular immunity, which uses the cytotoxic lymphocytes, to kill or control the HIV infected cells. While earlier work has concentrated on vaccines that induce antibodies, now a days efforts are made to reduce both arms of the immune system.

Current status of HIV vaccine

Several candidate vaccine have been developed and are in various stages of preclinical and clinical development. The first clinical trial phase I was performed in the US in 1987. Today more than 30 vaccine candidates have been tested in more than 80 clinical trials including more than 10,000 people. Most trials were done in the US and Europe, but also in developing countries like Cuba, Kenya, Brazil, China, Haiti, Uganda, Thialand and Trininad.

Encouraging result have been obtained usig the "prime boost" approach, in which a canarypox HIV vectored vaccine, which is known to induce considerable cell mediated immunity against HIV infected cells is being reinforced with a follow up dose of recombinant gp 120 subunit vaccine that generates a powerful neutralizing antibody response. A phase III trial started at the end of 2003 in Thialad enrolling more than 16,000 uninfected adults volunteers for the regimen ALVAC -boost gp 120 effectiveness. Several other trials are going on and we yhope that in coming few years we will come up with some potent vaccine which can offer both type of immunity and thus getting rid of this deadly disease called AIDS.

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Haemophilus influenzae type b conjugate vaccines - Its use and drawbacks

Normally in an immunization schedule we have till date seen 6 important vaccines consisting of BCG for tuberculosis, OPV for polio and DPT for diphtheria, tetanus and pertusis (whooping cough). In last few years hepatitis B vaccine has also been widely recommended.

Now when a parent visits a pediatrician for vaccination, they get a long list of vaccines to be given and this confuses the parents to a great extent in deciding whether to follow the doctors list or not. Among the vaccines prescribed other than those scheduled in EPI Hib or human influenza b vaccine is one of the most common vaccine.

When HiB vaccine should be started and it protects from which disease?

HiB vaccine protects against infection with N. infuezae bacterial infection which causes many diseases like otitis media, encephalitis and leaves permanent sequelae in the form of deafness or mental retardation in children.

A new born is protected from HiB by transplacental maternal antibody till 6-8 weeks. Acquired immunity develops in a baby only at 18 -24 months of age following subclinical infections. Hence the baby is susceptible from 6 weeks to 18 months and the HiB disease peaks during this period.

Which type of vaccine is HiB vaccine?

Hemophilus influenzae B is a capsular polysaccharide vaccine, so it is not a T cell dependent vaccine and there is no memory cell production. Hence there is no booster effect of this vccine when given for the second time. It is a B cell dependent vaccine, so only IgM is produced without IgG. So this is effective only in children above two years of age. On the contrary the disease prevalence of invasivw HiB disease is mostly below 18 months of age, with peak incidence around 6-9 months.

When a polysaccharide vaccine is conjugated with carrier protien, the conjugate vaccine will be effective from an earlier age even from 6 weeks of age, thus production against this disease is achieved from earlier age which is wanted. Now a days various conjugate vaccine HiB vaccines which are available, have made it possible to use HiB vaccine safely and effectively in the age when it is needed.

How long HiB vaccine is required to protect a child

The prevalence of Human influenza B disease is restricted to less than 5 years old children, hence two normal dose with a booster is sufficient to protect the child upto 5 years of age. Being a vaccine intended for boosting the immunity even the dosage are age related, for example 3 doses below 6 months, 2 doses between 7 to 11 months and a single dose after 1 year of age. All three schedules are followed by a booster dose AT 18 months of age. If HiB vaccine is administered for the first time beyond 15 months of age, a single dose is sufficient to evoke the required antibody response.

Can we postpone HiB vaccine to later age to reduce number of dosage

This is not advisable at all. The most vulnerable age of HiB infection is 6 weeks to 1 year. If the children are unprotected at this age then the whole purpose of HiB vaccination is not served. Mortality and morbidity are very hig if the child suffers from invasive HiB infection at a young and tender age.

What is the effect of HiB vaccination in India

In India the Indian acedemy of pediatrician has included HiB in the immuization schedule. It is given by a small percentage of pediatricians only in cities which covers only a small population. As HiB immunization is not in the Universal immunization program, nor it is given in any states or by any voluntary organization, so overall HiB coverage is meager in India.

Should HiB vaccination be considered in Expanded Program of Immunization (EPI) schedule in India

Though logistic is not supportive but if some voluntary organization come up with their support in any State then HiB vaccination should definitely be incorporated. In long run, considering the burden of disease, HiB should be included in National immunization program.

What are the formulation and combination of vaccines and is there any adverse effect

At present there are four formulations namely PRP-D, HbOC, PRP-OP and PRP-T. Three combiations are available in India namely DTwP/HiB, DTwP/Hepatitis B/HiB and DTap/HiB.

More details about HiB vaccine formulations, dosing, adverse effect etc can be seen at Types of HiB vaccine, its dosing and side effects.

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