Human Boca Virus and Child Health
Human Boca Virus, HBoV, Type 1 is now recognized to be the causative pathogen of the respiratory tract infections and diarrhea, which jeopardize child health in the early phase of childhood. HB0V type 2 and 4 are associated with acute viral gastroenteritis.
Respiratory tract infections are the leading cause of morbidity among infants and toddlers. Under 5 years of age, children suffers up to
8 episodes of respiratory tract infections every year.
Some of these episodes progress in to severe lower respiratory tract infections that demand hospital based management. Yet in about
20-40% of them, the underlying pathogen remains undetected.
This observation lead to the search for yet not discovered pathogen responsible for the most prevailing threat to child health.
In 2005 Allander et al. announced their discovery of HBoV, the Human Boca virus – a single stranded DNA virus from the family of Parvovirus.
The studies since 2005 to 2008, done on pediatric group, have shown -
1. HBoV is the commonest cause lower respiratory infection in children
≤ 5 years of age and >60% of those affected are ≤ 12 months of age.
2. Boys seem to be more frequently affected than girls – but more data is needed for confirmation of sex predominance if any.
3. 50% of the affected children develop lower respiratory tract infection, of which about 25% go into respiratory distress – Bronchiolitis like presentation.
4. It accounts for about 3% of all lower respiratory infection cases in pediatric age group.
5. Infants and toddlers (6 mo -2 yr) have higher incidence of HBoV positive samples nasopharyngeal aspirates, serum, feces and urine)
Human Boca virus induced respiratory infections in children are most noted in the months of March, April and May. The prevalence rate varies from 1.5 to 19% in different regions.
Presenting symptoms are –
1. Cough – most common. 25% of the cases develop pertussis like spasmodic cough
2. Nasal congestion
4. Difficulty in breathing
7. Less common are -
b. Rash –
i. Maculopapular erythema (small, reddish, flat elevated eruptions)
ii. Blanch on pressure
iii. Most commonly seen on chest, but few eruptions may be seen on face as well
Probiotics help shortening the clinical episodes.
As yet there is no specific anti-viral therapy recommended against Human Boca Virus. However studies conducted show a definite beneficial effect of Probiotics administration.
Probiotics shorten the duration of the episodes and diminishes the severity of symptoms by about 25 – 60%.
Therefore, at present, a daily dose of 10 raise to 10 colony units of Lactobacillus Acidophillus (NCFM) is recommended from November to April (both inclusive) every year. This can also be given in combination with Bifidobacterium Lactis (B1-07).
Both Lactobacilli and Bifidobateriun are generally considered safe for prolonged use.
However, they should be administered only in otherwise healthy children, under the supervision of treating doctor.
The incidence of HBoV1 infection in infants below 6 months is found to be significantly low. Most of the babies under 6 mo. are breast-fed. Human breast-milk is known to have prebiotic and probiotic properties.
Therefore, this 6 months regime of Probiotics may even be of prophylactic value in otherwise healthy children.
Long term consequences.
There is some concern that HBoV may be the cause of
1. Persistent wheezing disorder in children
2. Asthma - multiple attacks of acute exacerbation.
3. Frequent Otitis-media
4. Repeated Lower respiratory tract infections
The reports are convincing, but this discovery is yet in its infancy and more studies are needed to confirm the role of Human Boca Virus in chronic airway inflammation.