Tell-tale signs of neglect revealed by head lice
Release Date 12 December 2018
Looking more closely at lice and nits in the hair of victims of neglect could help unearth details of their suffering or even cause of death, new research has shown.
Scientists at the University of Reading demonstrated a new method to examine the hair of an elderly woman who had died in 2016 following serious neglect, and had a severe and untreated head lice infestation.
By assessing the biology of the lice and the number and position of their eggs (nits) in her hair, they were able to determine how long the woman had been neglected, the frequency of the neglect episodes and that she had been overdosing on medication before her death.
The researchers have produced a survey form to be used by medical professionals, teachers, social workers or family members to efficiently assess head lice infestations and to shed more light on cases of neglect.
"We should be routinely looking at head lice infestations in order to benefit from the reliable and unique clues they offer" - Dr Alejandra Perotti, University of Reading
M. Alejandra Perotti, Associate Professor in Invertebrate Biology at the University of Reading and lead researcher, said: “Analysing head lice and nits allows us to turn back time and draw conclusions about a victim’s suffering, even after their death. Lice offer a unique insight into the treatment of vulnerable people as their biology and behaviour are greatly influenced by the health of their host.”
“We should be routinely looking at head lice infestations in order to benefit from the reliable and unique clues they offer. In a forensic investigation, the more information we collect, the better the chances of uncovering the truth.”
Nit analysis provides clues
The research, by the University of Reading and the University of Pavia in Italy, is. It looks at the case of a woman who died hours after being admitted to hospital in Italy in a critical condition. Her very long hair and heavy louse infestation allowed the Reading scientists to carry out detailed analysis based on hair growth, nit accumulation over time and reproductive biology of female lice.
A total of 80 hairs were studied. Nit numbers, groups of nits and distribution of them on hairs from the severe infestation were compared with others taken from school children with regular infestations. The length of hair covered with nits and, an estimated rate of hair growth helped estimate the time length of the infestation; however, this should be applied with caution as hair growth varies with age and health status.
The number and distribution of nit groups on the woman’s hair carrying the heavy lice infestation revealed that she had been neglected for around two years. Female head lice lay eggs individually but, in severe infestations like this, female lice are so crowded that they lay eggs in groups or clusters. The hairs of the victim were almost totally covered with nits. Even at the tips of the hairs there was evidence of previous, sporadic lice infestations of scattered clusters suggesting she may have been repeatedly neglected.
The scientists found there were no nits within around 1.5-2cm of the scalp on the hairs; this is unusual, as head lice always lay eggs within 0.5cm of the scalp. The woman was known to have taken nifedipine – medication for high blood pressure – during the period of neglect. The active compound of this medication can prevent lice from laying eggs if they consume high enough doses through the blood of their host.
The nit-free gap at the base of the hair therefore suggested the woman had been overdosing on the medication and indicated that this had happened for roughly two months before she died, perhaps as an act of self-neglect.
Head lice are often found in the hair of victims of neglect, meaning they could offer useful evidence in many cases. However, they are currently rarely examined in this respect. The survey form produced by the team consists of a single page, and the researchers argue it should become common practice to record head lice infestations as such data is critical when assessing victims of abandonment and abuse.
Lambiase S, Perotti MA (2018). ‘Using human head lice to unravel neglect and cause of death’. Parasitology 1–7. DOI: