A bite in the playroom: Managing human bites in day care settings

Parents worry about the possibility of infections being transmitted to their children in day care settings. Physicians and health care workers need to have ready answers to these worries and queries. One area that causes concern is the frequency of biting incidents in day care and the possible transmission of infectious diseases such as viral hepatitis and human immunodeficiency virus (HIV).

SCOPE OF THE PROBLEM

Incidence

Even today, very little is known about the epidemiology of biting incidents in day care settings. In a study of child injuries in three Minneapolis centres (1), biting incidents were the most common injuries sustained by children, comprising 35% to 51% of all injuries reported by staff, with most incidents occurring in a facility caring for children diagnosed with behaviour problems.

A thorough review of the published literature on the subject of the epidemiology of biting unearthed only two systematic studies (2,3). Garrard et al (3), and Solomons and Elardo (2) prospectively followed cohorts of children enrolled in day care, using injury logs maintained by the staff to evaluate the incidence and severity of biting incidents and other injuries. Of 224 children followed in the Garrard et al study (3), 104 (46%) sustained 347 biting incidents over a one-year period. Of 133 children followed by Solomons and Elardo (2), 66 (50%) suffered 224 bites over 3.5 years. Most incidents were observed in September, and in the middle of the morning. The incidence rate varied with the age of children but not with sex, and toddlers (age 16 to 30 months in the Garrard et al study, age 13 to 24 months in the Solomons and Elardo study) sustained the most incidents, followed by infants and preschool children. The total bite rate in the Garrard et al study (3) (defined as the total number of bites per 100 child-days of enrolment in the centre) was calculated to be 1.5 bites per hundred child-days of attendance. Most injuries were to the upper extremities and the face. Only four in 224 bites (2%) broke the skin, with no incident resulting in referral to a physician for a bite injury (2).

These data and information obtained from other sources suggest that the approximate incidence of biting incidents in a day care setting with a full time enrolment of 60 children under three years of age approaches one biting episode per day, of which approximately one every 8 to 10 weeks would break the skin.

TRANSMISSION OF INFECTIOUS DISEASES

Bacterial infections

A human bite will rarely transmit a bacterial infection. Usually, the transmission of bacterial infections is associated with fighting incidents among adults. Severe bites are unusual in a day care setting and almost never lead to bacterial infections (4–6). In this context, the risk of transmitting a bacterial infection appears to be very low, and the usual precautions of wound care should decrease the risk of a bacterial infection to almost zero.

Viral infections

Hepatitis B:

Hepatitis B is usually transmitted through mucosal contact with blood and saliva from actively infected subjects. However, the virus is not transmitted by simple contact of saliva with normal skin. Only a bite resulting in skin breakage has the potential to transmit hepatitis B virus. There are several case reports in which hepatitis B was transmitted through a bite, and one relates to possible transmission in a day care setting (7). Another outbreak of hepatitis B described in a residential institution for the mentally retarded was probably related to a biting carrier (8).

A recent survey of hepatitis B markers among 1200 children in the province of Quebec found a very low prevalence of seropositivity (2%) at ages eight to 10 years, and no child in the group studied was positive for hepatitis B surface antigen (HBsAg) (9). The situation may be somewhat different in other areas of the country, but overall, the risk of transmission of hepatitis B from a biting child of unknown hepatitis B serological status appears to be extremely low.

However, an HBsAg-positive child who bites another and breaks the skin can expose the child who was bitten to infection with hepatitis B. Another high risk situation occurs if an unprotected child bites an HBsAg-positive one, with resulting blood contact with the mucosa of the biting child’s mouth. In these situations, appropriate preventive measures, such as the provision of hepatitis B immunoglobulin (HBIG) to the exposed, unimmunized child, should be undertaken (7).

Because of the extremely low prevalence of hepatitis B seropositivity in this age group, routine screening of children attending day care is not warranted. However, parents should be encouraged to disclose the HBsAg carrier status of their child to the day care personnel to allow personnel to implement proper prophylactic measures if another child is exposed (1,7,10).

HIV:

Transmission of HIV through a human bite is extremely unlikely (11). Saliva may contain some virus, but usually in extremely small quantities. Furthermore, the proteolytic enzymes present in saliva often inactivate any virus that may be present (11).

There are very few reports of HIV transmission through human bites or saliva in the literature (12,13). In one case, the mode of transmission of the infection between two siblings, although believed to be related to a bite, was unclear because the mother did not recall any skin break at the time of the incident (12). The second case reported involved multiple bites with very significant amounts of bloody contamination of the saliva (12).

Thus, transmission of HIV through biting incidents in the day care setting, even when minor skin breakage is involved, is extremely unlikely. In keeping with the recommendations of the Centers for Disease Control and Prevention, Atlanta, Georgia, postexposure prophylaxis after a human bite is not recommended (14).

FREQUENT BITERS

Frequent biters present a particular problem for day care operators. They should be managed on an individual basis, and this may involve behavioural interventions as well as modifications to the environment of the child. Biting is not likely to diminish by just ignoring an episode in an attempt to extinguish the behaviour because the biting child may experience positive reinforcement of his or her behaviour by making another child cry or relinquish a toy.

In general, measures that may help decrease biting incidents by frequent biters include

• avoidance of stressful situations and frustrations;

• firm statements to the biter on the negative impacts of his or her misconduct; and

• behavioral modification techniques such as ‘time-outs’ and positive reinforcement of appropriate behaviour.

RECOMMENDATIONS

1. Each day care facility should have written policies for managing child and employee illnesses and common injuries, such as bite wounds.

2. Day care centre administrators should take appropriate steps to limit the exposure of staff and children to blood and saliva. Hygiene practices should be implemented such as handwashing and separation of toothbrushes, in accordance with the accepted principles of universal precautions. Staff should be adequately trained and regularly updated in these matters, and in the proper care of minor wounds and injuries (15).

3. First aid equipment for the care of bite wounds should be available on site, and first-aid equipment, such as gloves, skin disinfectants and dressings, should be readily accessible.

4. If the skin is not broken, the wound should be cleaned with soap and water, cold compress should be applied and the child who was bitten gently soothed.

5. If the skin is broken (7,15),

   • the wound should be allowed to bleed gently;
   • the wound should be cleaned carefully with soap and water;
   • a mild antiseptic should be applied;
   • the child’s tetanus immunization should be reviewed and updated;
   • the parents should be notified;
   • an official report should be written and filed;
   • the wound should be observed over the next few days; and
   • if redness or swelling develops, the child’s parents should consult a health professional.

6. Prophylactic use of antibiotics should only be considered for deep wounds of the hand, wounds that cannot be adequately debrided or irrigated, and for facial wounds where excessive scarring from infection would be unacceptable. These are unlikely situations to be encountered in a day care setting.

7. If a known HBsAg carrier bites and breaks the skin of an unprotected (unvaccinated) child, HBIG and hepatitis B vaccine series should be administered. There is no medical need to test either the biting child or the bitten child for HBsAg before administering HBIG.

8. If a child who is known to be HIV-positive bites another child or is bitten by another child, the exposed child should receive prompt attention and care for the exposed area as described above. Considering the extremely low risk of transmission involved, prophylaxis with antiviral agents in combination is not warranted (14).

9. In the exceptional case where a biting incident results in exposure of buccal mucosa or broken skin to infected blood, the risk of transmission of HIV is still very low. A specialist in the care of HIV-infected children should be contacted for counselling.