09/03/2024 | News release | Distributed by Public on 09/03/2024 09:29
Catholic nuns aren't a population that many people would expect to be at risk of cervical cancer. Indeed, a widespread assumption that human papillomavirus (HPV) is only spread through sexual contact has meant that nuns and other religious groups aren't screened for it in some countries.
Yet, a recent study found that when nuns in Ghana were offered HPV testing, they had similar rates of high-risk HPV to women to the general Ghanaian population - highlighting the importance of giving all females access to cervical cancer screening and preventative measures.
Cervical cancer is the second most common female cancer in Ghana, killing approximately 1,700 women each year. The human papillomavirus (HPV) that causes it is very prevalent globally, and while only a small percentage of HPV infections progress to cancer, detecting and treating precancerous cells, and preventing infections from occurring in the first place can have a huge impact on rates of cervical and other HPV-related cancers.
Yet, with no structured national cervical precancer screening programme in Ghana, most women must pay for this service and travel long distances to receive it. The HPV vaccine, which prevents cervical and other HPV-associated cancers, is also only currently available for those who can pay, as it has not yet been included in Ghana's routine immunisation programme.
Research from other low- and middle-income countries has suggested that nuns and other religious females are sometimes excluded from cervical cancer screening. "In the extreme scenario, they have been denied primary prevention through vaccination against high-risk HPV," said Dr Kofi Effah, a gynaecologist and head of the Cervical Cancer Prevention and Training Centre at the Catholic Hospital in Battor, Ghana.
"It is known that high-risk HPV can be transmitted through non-sexual means, but many seem not to be aware of this, including senior professionals in the field. These people would misinform nuns that they have no risk of high-risk HPV infection and did not need screening. Some created a stigma, linking high-risk HPV infection to sexual activity."
A recent initiative to offer free HPV testing for 10,000 women across Ghana and Nigeria provided Effah and his colleagues with an opportunity to screen this group of women. "Our main aim was to offer cervical cancer prevention services to a group at risk of cervical cancer that might have been ignored," he said.
With the permission of the Mother Superiors, they visited convents in the Greater Accra, Volta and Central regions of Ghana, and offered nuns the opportunity to self-collect cervical samples for HPV testing, under the supervision of a trained nurse. One hundred and five women did so, of whom 25 tested positive for high-risk HPV - a prevalence of 23.8%. This HPV-positivity rate is similar to that of the general Ghanaian population.
Those nuns who tested positive were offered Pap smears and a diagnostic procedure called a colposcopy to check for abnormal cells, with clinically relevant changes detected in two of them. However, follow-up tests suggested they were healthy.
"This study highlights the need to include nuns in general cervical precancer screening programmes in Ghana, despite the historical and anecdotal perspective that cervical cancer is rare among them," said Effah.
Although the nurses that screened the nuns didn't ask them about their sexual histories, and it is possible that they acquired the virus through sexual contact, there are other ways through which they could have got the infection.
Though relatively rare, HPV can be transmitted vertically from mother to child during delivery, as the baby passes through the genital tract. "We see many cases of women with genital warts and children (girls and boys) with vulval or anal warts," said Effah. "What proportion of these is from vertical transmission needs to be studied, especially in a country like Ghana that has never started a national HPV vaccination programme."
Another means of non-sexual HPV transmission could be the use, or sharing of, bulb syringes for enemas - where liquid is injected directly into the rectum to relieve constipation, or as a remedy for various ailments, according to traditional west African medicine.
"The use of bulb syringes (bentua) is common in Ghana and in many families the bulb syringes are shared by family members, including children," said Effah.
Earlier studies have shown that the virus can survive on inanimate objects, including toilet seats, medical equipment and bathroom surfaces. HPV has also been detected on people's fingertips, raising the possibility of them infecting their own genitals - although this has not been proven.
Prof Alan Nyitray, who studies HPV-associated disease at the Medical College of Wisconsin, US, said that, while a man's penis is considered the main vehicle for HPV transmission - particularly to the anal and genital area - non-penetrative sexual behaviour such as hand-to-genital contact, could conceivably spread the infection, and non-sexual transmission may sometimes occur.
His own research, which drew on data from the HPV Infection in Men (HIM) Study, has found HPV in male virgins from Brazil, Mexico and the US, although it is possible they got it through non-penetrative sexual behaviour. This research also showed how quickly men were infected once they started having sex: 29% had been infected with HPV within one year, and 46% within two years, reflecting the highly infectious nature of the virus.
"People shouldn't believe that it is very common for HPV to be transmitted non-sexually, but they should also know that it can happen - and that HPV infection doesn't only happen to people who have had lots of sexual partners. You can be infected if you've only had one sexual partner," Nyitray said.
"This in turn tells us that, regardless of what someone thinks their children's sexual behaviour will be in the future, they should be vaccinated."
Effah's study, which was published in eClinicalMedicine, also highlights the potential for innovations such as cervical self-sampling to reach women in religious groups, including nuns, who are at an almost equal risk of cervical cancer, but may miss screening due to many factors, including lack of information on their risk. They may also be less willing to undergo a pelvic examination.
"Self-sampling is a simple approach that nuns can use and supports their right to health," Effah said.
Although some studies have suggested a slightly lower accuracy for HPV testing using self-samples compared to health worker-collected samples, this is potentially compensated for by a higher willingness among women to take part in screening, he added.