Treating head lice

Editor - We felt there were a number of fundamental omissions and
errors in this article.

This was an excerpt from an American resource ‘Best Treatment’. The
‘Treatments that are likely to work’ were listed as malathion, lindane,
permethrin and pyrethrins. The author did not list carbaryl, which is a
useful prescription-only medication frequently used in the United Kingdom,
especially when resistance to the other pediculocides is suspected.
Malathion is generally very effective if correctly applied, and although
shampoo preparations requiring only a 5-minute contact time are available
in the UK, we would generally recommend the use of lotion or liquid with a
12-hour contact time. Phenothrin (marketed in the UK as Full MarksÒ) and
Permethrin (LyclearÒ) are both pyrethroids. Again a 12-hour contact
formulation is preferable. In the UK a repellent spray known as RappellÒ
is available, but its’ efficacy is uncertain (BNF). Lindane is not
included in the British National Formulary

When discussing the lack of evidence to support ‘bug busting’ as a
control measure the article cites a study which compared the use of
malathion to combing, stating that malathion was more effective. The
sample size for each study group was very small and would have made
interpretation of the findings difficult to validate. The reference for
this study was not given. It is certainly true that many combs that are
available will not be effective as the teeth are too short to penetrate
the full thickness of the hair at each stroke. We would agree that further
study is needed to fully evaluate the efficacy of the various headlouse
combs available to the public at the current time. Many are little more
than expensive gimmicks.

The article states that headlice away from the head are non-viable.
Our own experience is rather different from this and we believe the issue
needs further research. We have circumstantial evidence indicating that
headlice may, rarely, be transmitted via fomites such as hairdressing
equipment. We have observed during detection combing that headlice at all
stages of maturity, removed from a scalp during combing can orientate
themselves and ascend towards the head. A headlouse that, having been
forcibly removed from one head (eg during detection combing), is placed at
waist level on another person will move towards the head and we have found
it can re-establish its’ lifestyle. Chunge et al.1 showed that headlice
removed from children’s heads survived at room temperature for an average
of 21.3± SD 12.1 hours although the ability to re-establish the life cycle
was not examined.

Headlouse infestation causes a high degree of anxiety, humiliation
and frustration to families across the UK. The parents’ commentary
accompanying the article barely touched on the issues that impinge on the
management of this ‘common harmless condition’. We would challenge the
statement that it is a ‘harmless’ condition when it affects parents’
relationships with their children, their partners, and health and
education professionals. Children who have ongoing headlouse infestation
may have poor concentration at school if they are not sleeping at night
due to scalp irritation or secondary bacterial infection. They will
frequently be bullied or socially isolated at school when peers are aware
of their heavy headlouse infestation.

In rare cases, ongoing headlouse infestation may be an indicator of
more fundamental parenting issues and may be a component of other clinical
scenarios such as psychiatric disorder affecting the child’s carer. It is
also important for the health professional to recognise that a few
families will not consider headlouse infestation as abnormal.

None of the papers mentioned the fundamental importance that
effective contact tracing has on the management of headlouse infestation.
The application of an insecticidal lotion will have no deterrent action,
so the problem will recur unless the source of the infestation is
identified and effectively treated. For this reason we always advise the
full detection combing of all close contacts when a person is identified
as having headlice. This can be very complex in some families, especially
if there are communication problems between the main carers.

Ideally any affected people must be treated using the same type of
lotion within the same 24-hour period. Once a person has been identified
as having headlice, carers should be aware that reinfestation may occur.
For this reason, detection combing we believe should be built into the
regular grooming routine. Ideally detection combing should be done 2-3
times a week. If a few mature headlice are found, the frequency of combing
should increase to daily. If all mature headlice are removed, lotions are
not necessary, but continued combing is – to ensure the removal of newly
hatched lice before they reach maturity. Combing must be continued until
no more lice are found.

We have noted that the general public have attributed erroneous
properties to the conditioners used to facilitate regular combing. Some
parents allow the conditioner to dry on the hair believing it to have
repellent properties. This should be discouraged, as dermatitis or
trichological problems may ensue.

The successful treatment of headlouse infestation relies on
commitment. Whether infestation is treated by the use of lotions or by
frequent combing, ongoing vigilance is necessary in order to facilitate
the early detection and treatment of reinfestation when it occurs.

1. Chunge et al. A pilot study to investigate the transmission of
headlice. Can J Public Health 1991;82:207-8)

Competing interests:  
None declared

There is no doubt in my mind that the chemical pesticides are proving
increasingly ineffective locally (S.W. Wales). This is hardly surprising
as many parents are unaware that they should not use these chemicals
unless active infestation is found. Indeed, those dreaded school letters,
informing parents of head lice in the class, may actually be perpetuating
the problem. Why have there not been any new, more efficacious, less toxic
topical treatments been developed over the last few decades?

Market forces
are clearly a huge driving force, plus the fact that, as your article
points out, head lice are not life threatening. But, as a parent, with a
background in pharmaceutical research, I became curious when my 3 year old
contracted head lice and I discovered a apparently pesticide resistant
head lice population. Your article alludes to the possible need for
repeat treatments. My understanding is that no treatment is 100%
ovicidal, so repeat treatments are imperative, yet sale of single
treatments continue. You refer to little evidence for efficacy of herbal
remedies. Indeed, although my background would tell me that double blind
placebo controlled studies are necessary to prove both safety and efficacy
of such treatments, my frustration led me to test out 'natural remedies'
on my family (I already had an interest in essential oils).

I was quite
amazed by my findings. In short, after considerable reading, some hand-on
experience and many second-hand reports I would contend that 1) coating
lice in any viscous oil will block their spiracles, effectively
suffocating them, 2)utilising essential oils at an appropriate dilution
will disorientate most of the lice and even kill a good proportion, 3)
treating with neem oil (or leaf extract) at an appropriate dilution will
disrupt the breeding cycle and development process, hence ultimately prove
fatal to the lice. Head lice are not of huge concern for pharmaceutical
companies, but are terribly frustrating for a large number of parents,
many of whom continue to waste their money on ineffective OTC treatments.

When will it stop?

Competing interests:  
None declared

To take up the proposition offered by Sylva Dolenska on the
intervention of the school nurse, it might be of interest to her that in
the early 80's there was a changeover in policy here in sunny 'ol West
Yorks which meant that the routine rounds of the beloved "Nit-Nurse" no
longer took place.

Now this in conjunction with the perhaps locally held belief that
lice were associated with poverty and lack of grooming led to an
underground and often unrecognised explosion of the little dears in our
schools and amongst families that could not conceive of such an
infestation touching their family. The perceived social stigma encouraged
lack of communication of individual cases by parents to the school or by
the school to other parents. Lack of appropriate information or experience
quite often led to a complete inability to detect them at the early stage.

I feel a whole generation of children grew up with parents and if I
might say so, GPs' unable to recognise a louse unless the little darlings
were at the positively teeming stage hence more likely to be passed on.

So Malathion, Permethrin etc were thrown at them with alarming
frequency and no obvious benefit as re-infestation was almost a certainty,
the source was unlikely to make itself known and the merry-go-round would
begin again.

There is good reason to suppose that this was in part within the
family itself as often parents would not treat themselves for a variety of
reasons but would quite happily hurtle to the nearest chemist and
liberally dose the child in their organo-phosphate of choice.

The welcome stance taken by Leeds in the past few years might prove
effective in other areas if the "dirty" image were well and truly laid to
rest by more active campaigning by schools and local health practices
including education of parents and children by frank discussion in the
school and home. Though as has been noted, it should be stressed that
while Lice are not life threatening, the potential for scalp irritation
and secondary infections could be highlighted lending added weight to the
argument that they need to be dealt with.

The thorough wet combing of every family members hair as a norm at
EVERY bathing whether needed or not should be actively encouraged,
breaking the lifecycle of the blessed things, no special shampoo or
conditioner is needed, though the alleged anti-bacterial properties of
some essential oils seem to help with minor scalp irritation. As a nation
we spend millions on hair products but spend so little time on this basic
preventative measure. Though I actively loathed my Nonna and her vicious
metal comb as a child, the culture and tradition is one that I’m grateful
for.

As for my observation being well researched (?) I can only cite
experience of my own four children and being all too often called in by
neighbours, friends (and in some cases people I was barely acquainted
with) on the verge of tears to come and inspect their childrens’ hair as
they hadn’t a clue what to look for. There’s a lot to be said for communal
grooming sessions, coming down from the trees is optional.

Regards
MCF

Competing interests:  
None declared

Dear Sir,

Here in Brazil we have the same problem with head lice infestation
that is described by the Commentary and the Editor's choice of BMJ. We
don't have any pediculicides with Malathion or Carbaryl in our country but
only Permethrim rinse cream or Deltamethrim shampoo, and a lot of strains
of head lice resistant against both products.

The review, the letters and the editorial were very interesting, but I
think that there was not emphasis on the importance of the treatment
against head lice, which must be collective with all infested children
treated at the same time to avoid reinfestation and a second treatment 10
days later to kill the nymphs emerged from the nits that remained alive on
the first treatment.

Competing interests:  
None declared