‘Greater effectiveness, lower cost should be main goals for vaccine-makers’

Vaccines have been part of the human fight against disease for more than 200 years and are a simple, safe, and effective way of protecting you against harmful diseases, before you come into contact with them. It uses your body’s natural defences to build resistance to specific infections and makes your immune system stronger.

These views were shared by Prof Khalid Shafi, renowned consultant paediatrician and general secretary of the Pakistan Paediatric Association, at a public awareness seminar titled ‘Future of Vaccines’, which was held recently.

“When you think of vaccination, you probably think of a doctor or nurse administering a shot, future immunization delivery methods, however, may differ from what we use today. Inhaled vaccines, for example, are already used in some cases: influenza vaccines have been made in a nasal spray. One of these vaccines is available every year for seasonal flu,” he said while addressing the seminar held at Dr Essa Laboratory & Diagnostic Center, DHA.

“Other possibilities include a patch application, where a patch containing a matrix of extremely tiny needles delivers a vaccine without the use of a syringe. This method of delivery could be particularly useful in remote areas, as its application would not require a trained medical person, which is generally needed for vaccines delivered as a shot by syringe, multiple respiratory infections called tripledemic, could be covered by a single injection, allowing vulnerable people to be protected against Covid, flu and respiratory syncytial virus,” explained by Prof. Khalid Shafi.

Guest speaker Dr Altaf Hussain, consultant paediatrician and neonatologist, highlighted the benefits and future directions of the Expanded Programme on Immunization (EPI). According to the expert, EPI covers vaccination services implemented in order to ensure the immunization of all vulnerable age groups by preventively reaching out to them before they contract and develop infectious diseases, notably pertussis, diphtheria, tetanus, measles, rubella, mumps, tuberculosis, polio, chickenpox, and hepatitis A and B.

Rota vaccine was introduced in 2017 and typhoid conjugated vaccine (TCV) in 2019 in Sindh and was introduced in Punjab and Islamabad in 2021. The measles vaccine is being replaced by Measles Rubella (MR), which also protects against rubella and congenital rubella syndrome (CRS).

“EPI can have a vital role in the fight against antimicrobial resistance. If you can stop people from catching infections, you can reduce the number of antibiotics being used. And the fewer antibiotics are used, the lower the chance of resistance developing,” Dr Altaf Hussain said.

Earlier, addressing the inaugural session, Dr Farhan Essa Abdullah, infectious disease specialist and CEO of Dr Essa Laboratory, said millions of lives could be saved by a groundbreaking set of new vaccines for a range of conditions, including deadliest diseases like cancer, cardiovascular and autoimmune diseases, which will likely be ready by 2030, while recent studies into these vaccines are also showing tremendous results.

Currently, an estimated 19.3 million new cancer cases have been diagnosed worldwide, with around 10.0 million cancer deaths annually.

“When you have rheumatoid arthritis (RA), you face more than sore and swollen joints. The autoimmune disease can affect your whole body, including your organs, and make you feel lousy all over. In the future, an RA ‘vaccine’ and other drugs that affect your immune system may be an option, 18 million people worldwide were living with rheumatoid arthritis & 70% of them are women,” added by Dr Farhan Essa.

The seminar was told that while we can attribute many public health successes to vaccination, the future presents continued challenges. Diseases remain for which researchers have been unable to find effective vaccines such as HIV, tuberculosis, malaria and leishmaniasis remain a tough task. One of the primary reasons for this is that the viruses, bacteria and parasites causing these infections hide from the immune system inside the person’s cells. To overcome this, a different kind of immune response involving T cells is required instead of, or in addition to, an antibody response.

There are some infections associated with serious long-term complications that we don’t yet have a vaccine for. For instance, infection with the bacterium Helicobacter pylori means patients are more likely to develop stomach cancer, and group A streptococcus infection is responsible for rheumatic fever, which is still a significant cause of death and disability in developing countries.

Based on experience with emerging infections like Ebola and Zika, progress has been made in developing vaccines that can stimulate some of our own cells to temporarily produce antigens.

In the case of tumors, the vaccine can either be directed against the tumour itself or be designed to amplify the anti-tumour immune response. For autoimmune or allergic disorders, vaccines are being designed to switch off unwanted immune responses rather than switching on the useful immune response needed for infections and cancer, while promising trials are in progress for vaccines to treat nicotine and cocaine addictions.

“Although many current vaccines are highly effective, efforts continue to develop vaccines that are more effective than those available today. Thus, researchers continue to explore new possibilities. Greater effectiveness, lower cost, and convenient delivery are some of the main goals; another issue researchers are trying to address is the so-called cold chain problem. Many vaccines require cool storage temperatures to remain viable. Unfortunately, temperature-controlled storage is often unavailable in parts of the world including Pakistan where vaccination is vital for disease control. One of the reasons smallpox eradications was successful was that the smallpox vaccine could be stored at relatively high temperatures and remain viable for reasonable periods,” Dr Farhan elaborated.