Spare some thought for immunodeficient patients — Bruce Lim

DECEMBER 31 — Primary immune deficient (PID) patients, more so than the general population in Malaysia are alarmed by the news of first polio outbreak in Sabah recently. Unlike the average population who have normal immune function (immunocompetent), PID patients have a weakened immune function (immune deficient); the latter are unable to develop immunity even with immunisation. Hence it is redundant to have the PID patient immunised; in fact, immunisation in certain types of primary immunodeficiencies could do more harm to the patients. A case in point is the oral polio vaccination (OPV). Unlike the general immunocompetent population, OPV is contraindicated for patients with certain types of PID; for when given OPV, the PID patient will be afflicted with polio disease. On the other hand, the immunocompetent general population will be protected from the disease with oral polio vaccination.

Basic mechanism of immunity

Let us explore the immune mechanism of how introducing part of the offending organism (antigen), either inactivated (killed) or attenuated (altered) is effective in provoking the immune system into making particular antibodies that will fight or prevent the associated infection.

The reason why so many communicable diseases (measles, TB, polio, etc.) are preventable with vaccination is the amazing immune system’s ability to protect the human body from a disease. The immune system in a normal host can ‘learn' how to protect one self, by recognising the dangerous micro-organism and build strategies (for example, building antibodies and white cells) to prevent a disease. With every exposure, the damage becomes lesser as memory is created; the antibodies and white cells recognise the specific germ and respond immediately to destroy the invader. These are the reasons why some vaccines such as vaccines against diphtheria, pertussis and tetanus are given at repeated doses at specified intervals. A single dose alone is unlikely to be sufficient.

The same cannot be said for immune deficient patients, namely primary immunodeficiencies (PID) and secondary/ acquired immune deficiencies (HIV infection, severe malnutrition, cancers on Immunosupressed therapy). Their immune system is weakened and in some absent. Hence they have no defence against harmful micro-organism. For temporary protection, certain types of PID depend on regular infusion of commercial Immunoglobulins (antibodies), some require prophylactic antibiotics and in some a bone marrow transplant is needed. In PID, the immune deficiency is permanent while in secondary it is not.

From statements made by the Ministry of Health Malaysia (KKM) and write ups from expert groups through the news in the media, the evidence points to the following:

  • The strain responsible for the polio outbreak is circulating vaccine — derived poliovirus type I (cVDPV 1). It could only originate from the live attenuated oral polio vaccine (OPV)
  • OPV is still being used in the Philippines. In 2008, Malaysia switched to the inactivated polio vaccine
  • It is reported that the three-month-old infant infected with polio has no travel history, nor the family. It is therefore likely to have been introduced by the unvaccinated individuals (could be migrants)
  • An investigation by KKM shows that 23 out of 199 children are not vaccinated against polio
  • The implicated polio strain only occurs if the population is under immunised
  • The risk of disease from such strain is especially high in PID patients.

We, the patients within MyPOPI (Malaysian Patient Organisation for Primary Immunodeficiencies) together with MSAI (Malaysian Society of Allergy and Immunology) and MyPIN (Malaysian Primary Immunnodeficiency Network, a like-minded group of professionals concerned with PID patient care) contend that:

  1. The index polio child with flaccid paralysis should undergo tests to exclude PID especially the most severe form ie severe combined immunodeficiencies (SCID). This is especially when vaccine strain infection is one of the known manifestations of PID as well as due to the immunodeficient states.
  2. An effort should be made to exclude PID within the immediate community and also the 23 children who were not vaccinated.

Advice should always be sought from a specialist immunologist before PID patient has an immunisation. Not only the risk of contracting the disease  from the  circulating vaccine — derived poliovirus type I (cVDPV 1), is high in the PID patient, when afflicted PID patient continues to shed the virus.

How could this happen when > 90 per cent of Malaysians are vaccinated against polio? The only plausible explanation of the re-emergence of polio disease attributable to the vaccine derived polio virus cVDPV 1 (harmless to normal individual), is that it had infected someone with immune deficiency causing the outbreak and continuing to shed the virus via faecal oral route.

To the almost 300 ‘recorded‘ patients as PID in MyPIN registry, this is a nightmare. This is only the tip of the iceberg. What about the bulk of PID patients who are undiagnosed, underdiagnosed or worst misdiagnosed nationwide? That would remain anyone's guess.

When exposed to the present vaccine derived polio strain they end up with the disease (polio). They are also at risk if immediate family members having recently been immunised with the live vaccine (OPV) shed the vaccine derived virus through faecal-oral route. There is no cure for polio, it can only be prevented.

That is the predicament of the PID community.

It does not help matters when PID which has been established as a chapter in current textbooks of medicine and recognised as a disease group internationally is treated like an orphan in Malaysia. Although the first PID in Malaysia was reported as early as in 1977, with the second wave in mid-1980 at the same time HIV made its presence felt, policy makers put full attention on HIV control programme neglecting PID, which resulted in an increasing number of HIV detected in all states including Sabah and Sarawak. Meanwhile HIV infections have reduced in numbers. More importantly the mortality of HIV-AIDs is only a fraction of PID mortality.

The best option for good management and care of PID lies under the purview and responsibility of clinical immunologist (the recommended ratio is two per million population). Presently there are only five clinical immunologists in Malaysia, the very few medical specialists who underwent further training in immunology (clinical) in reputed centres overseas, on both sides of the Atlantic and in the Oceania. All have served for many years, some for more than a few decades in Malaysia without due recognition. They are known internationally but not recognised at home.

How do we then address the shortage of clinical immunologists in our country? Empower them to lead the training of human capital via a subspecialty clinical immunology programme. Expedite recognition by NSR which had been submitted twice, the first in 2011. That is the only way to expedite the pool of credible clinical immunologists needed for the nation.

PID patients in Malaysia have waited patiently to also receive expeditious health care facilities and amenities afforded to similar group of diseases such as Thalassemia and Haemophilia. For the PID patient access to Immunoglobulin therapy including the subcutaneous route, (antibody deficiency), cytokine therapy (gamma interferon) for CGD (chronic ganulomatous disease) should be expedited.

There must be democratisation of PID facilities towards East Malaysia. Sarawak and Sabah have seen a significant rise in the detection of new PID cases. Clinical and diagnostic laboratory immunology facilities under the supervision of clinical immunologist is sorely needed. So is bone marrow transplant service for severe combined immune deficiency patients.

PID patients in Malaysia have waited long enough at a considerable cost of severe morbidity and high mortality unknowingly to the rest of the communities in Malaysia. PID patients in Malaysia deserve the best care and nothing less.

*Bruce Lim is the president of MyPOPI, a non-profit organisation that supports and represents people affected by primary immunodeficiencies (PIDs) in Malaysia.

*This is the personal opinion of the writer or publication and does not necessarily represent the views of Malay Mail.


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