Guyana gets breakthrough in tackling HPV

Jan 10, 2009 News

---

…testing to begin in a few weeks

By Melanie Allicock

“The general public will be able to access the HPV rapid tests in the same way that they are able to access HIV tests,”—Minister Ramsammy

Guyana is to record a landmark initiative, in another few weeks, with the introduction of rapid testing for the Human Papilloma Virus (HPV).
Health Minister Dr Leslie Ramsammy has, for the past two years, been wrestling with factors crucial to the initiation of tackling the presence of HPV among Guyanese.
The Human Papilloma Virus (HPV) is sexually transmitted, and is one cause of cervical cancer.
The two main bugbears have been negotiating for the most lucrative conditionality under which to purchase the newly available quadrivalent vaccine, Gardasil, and determining the specific genotypes of the virus present in Guyana.
Being able to afford the exorbitant cost for conducting the relevant tests to inform women whether they are at risk of developing cancer, or already have the disease, has also proven problematic for the local health sector.
However, with the recent approval by the Food and Drug Administration, the United States federal regulatory body for the use of rapid testing for HPV, Guyana’s task in the area of testing has been made easier.
This new venture is part of an overall programme aimed at early detection and identification of women with precancerous conditions, Dr Ramsammy noted.
“We are working towards making all the interventions in cancer available to the public. Radiotherapy and chemotherapy are already in place.”
Approximately 20 million people worldwide are currently infected with HPV. At least 50 percent of sexually active men and women acquire genital HPV infection at some point in their lives.
By age 50, at least 80 percent of women will have acquired genital HPV infection.
The VIA (visual inspection with ascetic acid) method of screening for cervical cancer has also been introduced, but at the moment only a few women have benefited from this type of intervention.
The VIA method, which is only being used in a few countries, involves the use of the acid on a spate to detect precancerous conditions.
Once the conditions apply, an electro-surgical intervention is performed shortly after on the affected area.
Dr Ramsammy said that this technique is cheap and has proven 100 per cent effective on the few women on which it has been performed.
He explained that, unlike Pap smear testing, this procedure is direct, less complicated and quicker.
Noting that prevention is now the challenge for Guyana, the minister said that it is in this regard that the HPV testing is being introduced to avert the incidences of its prevalence.
Pap smear tests being done in Guyana at the moment only identify the presence of cervical cancer, and do not test specifically for the presence of the HPV, since this requires specialised equipment.
However, any abnormalities identified in the cells of the cervix, which in many cases are the symptoms of cancer caused by the undetected HPV virus, are treated.
The incidence of cervical cancer in Latin America and the Caribbean is said to double that of the developed countries. In Guyana, the leading type of cancer among women is that of the cervix.
The types of HPV that infect the genital area are spread primarily through genital contact.
Most HPV infections have no signs or symptoms; therefore, most infected persons are unaware they are infected, yet they can transmit the virus to a sex partner.
HPV testing
Prior, testing for HPV was done solely using the Polymerase Chain Reaction (PCR) technique widely used in molecular biology.
Developed in 1984 by Kary Mullis, PCR is now a common and often indispensable technique used in medical and biological research labs for a variety of applications. While this type of testing has proven extremely reliable, it is extremely costly.
Noting that the Health Ministry is grasping the opportunity of a cheaper method of testing, Dr Ramsammy, however, expressed optimism that the rapid testing will prove just as effective as the PCR.
“We are at present putting the protocol together, after which we will conduct tests using both methods, with the aim of evaluating the effectiveness of the rapid tests… I am however very confident that this rapid testing will be just as effective, and we can finally move forward with fighting HPV in Guyana.”
The testing will first be introduced into the ante natal population, according to the minister.
At the outset, only women involved in the Prevention of Mother to Child Transmission Programme (PMTCT) will have access to the HPV testing free of cost.
It will then be gradually introduced across the board, where all women of reproductive age will be able to request the rapid tests.
“The general public will be able to access the rapid tests in the same way that they are able to access HIV tests,” the minister said.
He noted that, in the past, cervical cancer was thought to be a non-communicable chronic disease, but today it is understood that it is communicable, and therefore preventable.
“Since cervical cancer is one of the sexually transmitted diseases, before the introduction of the tests in another couple of weeks, the same education and awareness activities being undertaken in the fight against HIV/AIDS will be used in this programme,” the minister said.
HPV and Gardasil
HPV-induced cervical cancer remains the fifth most common cancer in women worldwide, intensifying the need for the use of a preventative vaccine.
Guyana has already made its decision to use Gardasil to protect against HPV.
And since vaccination and testing should work in tandem if the programme is to be effective, foreign medical experts, in collaboration with local practitioners, are at the moment wrapping up studies aimed at determining the specific genotypes of the virus present in Guyana.
There are more than 200 strains of the virus, and the vaccine is only fully effective against certain types, even though it provides limited overall coverage.
“The vaccine will give you overall protection up to about 70 per cent against certain types, but it will give about 99 per cent for specific strains, and we need to demonstrate up front what our types are.”
The cost for a single dose of the vaccine is somewhere in the vicinity of US$360, but through its collaboration with such entities as GAVI and PATH in Seattle, USA, as well as with financial assistance from PAHO/WHO and UNICEF, the cost to Guyana would be in the single digits, according to Dr Ramsammy.
The minister is also actively lobbying for the vaccine to be part of the funded vaccination programmes from GAVI, which provides the pneumococcal and rotavirus inoculations to Guyana.
The most effective use of the vaccine would be before the initiation of sexual activity; it will therefore be given to girls between nine and 11 years old.
The minister explained that of the more than 200 known HPV types, 37 are known to be transmitted through sexual contact, and infection with sexually transmitted HPVs is very common in adult populations worldwide.
Although a few HPVs, such as types 6 and 11, can cause genital warts, most genital HPV infections come and go without ever causing any symptoms.
However, lingering infections with a subset of about 19 “high-risk” HPV types can lead to the development of cervical cancer or other genital/anal cancers.
Some forms of HPV have been found to be associated with a form of throat cancer.
Only a small percentage of women with HPV go on to develop cervical cancer.
According to Dr Ramsammy, the latest generation of preventive HPV vaccines is based on hollow virus-like particles (VLPs) assembled from recombinant HPV coat proteins. The vaccines target the two most common high-risk HPVs.
The vaccines have been shown to offer 100 percent protection against the development of cervical pre-cancers and genital warts caused by the HPV types in the vaccine, with few or no side effects.
The protective effects of the vaccine are expected to last a minimum of 4.5 years after the initial vaccination.
The minister noted that, in developed countries, the widespread use of good-quality cervical “pap smear” screening programmes has reduced the incidence of invasive cervical cancer by 50 per cent or more.
“It is therefore important that women combine the benefits of both programmes by seeking regular pap smear screening, even after vaccination.”
What is HPV
The Human Papilloma Virus, which is passed on through sexual intercourse,
lives in the skin or mucous membranes, and usually causes no symptoms.
Some people get visible genital warts, or have pre-cancerous changes in the cervix, vulva, anus, or penis. Very rarely does HPV infection result in anal or genital cancers.
There is no “cure” for HPV infection, although in most women the infection goes away on its own.
Rarely can a pregnant woman pass HPV to her baby during vaginal delivery.

---

---