"Head lice have been with us for several millennia, and are likely to continue well into this one," says Taplin. "In fact, with the continued population expansion worldwide and the movement of people into overcrowded urban areas, many areas of the world will experience even higher prevalence. The high cost of products produced in the 'developed' world make them unavailable to most of the world's population. The speed and increased use of air travel guarantees transfer from highly endemic areas to more affluent countries."

Maunder and Mumcuoglu agree that there is no indication lice will be eradicated anytime soon.

According to these experts, head lice are just as prevalent today as they were sixty years ago. In fact, treatment-resistant lice, or "super lice" as school nurses have referred to them, are known to have appeared in Europe, the United States and the Middle East, according to Taplin.

In Israel, Mumcuoglu notes, "in the past 15 years, 15 to 20 percent of all children aged four to 12 were infested with lice and eggs at any one time. Another 20 to 25 percent had nits only. Shortly after the introduction of permethrin-based treatments, in the early 1980s, there was a 60 percent decrease in infestation. But the percentage rose again two years later when local lice developed a resistance to permethrin."

Maunder agreed, citing an upsurge in head lice infestations in the United Kingdom, peaking at a high of four to five percent in 1996 and now holding steady at roughly two to three percent of the school age population. Maunder speculates the upsurge and continuing problem are caused both by insecticide resistance, and the reorganization of the country's National Health Service.

"With the reorganization, the school 'nit nurse', whose role it was to check each child's head, disappeared, as did general health education for families," he affirms.

The problem has been perceived as so severe in the UK for several years that October 31 has been declared National Bug Busting Day, to prompt parents to check their children's heads for lice.

In the U.S., Taplin notes, "Miami is no different from most U.S. and European communities or the countries of Central and South America where we also work."

All of the experts agreed there are no "lice free" areas of the world. Historically, according to Taplin and Mumcuoglu, during wars, natural and man-made disasters, when people are living in overcrowded conditions, all kinds of parasitic infestations are common, including head lice. So, during World Wars I and II, there were head lice "pandemics." During the 1950s and 60s, notes Mumcuoglu, head lice became rare, but eventually, children from all socio-economic levels again became infested.

"However uncomfortable today's problem is, we HAVE come a long way in treatment of this problem in western civilization in the last century," notes Maunder. "Contemporary perceptions of epidemics are nowhere near the actual epidemic conditions of the nineteenth century. For example, in 1870, 90 percent of all children in England could be infested with head lice at any given moment. Today's levels are a fraction of that. But that incidence has become unacceptable in modern society."

Today's most common head lice treatments--in the geographic areas the experts focus on--range from a variety of over-the-counter synergized pyrethrins and pyrethroids (in shampoo or lotion forms) to malathion lotions and carbaryl shampoo (mostly in the UK and Israel). Unfortunately, none of these current treatments can completely eliminate head lice. Why?

First, "shampoos do not work, anywhere," says the UK's Maunder. "Contact time between the treatment and the problem (the head louse) is too short--it would take at least six hours' exposure to eliminate the lice."

Both Taplin and Maunder note that "malathion lotion is very effective, but requires a prescription and a 12-hour treatment." Malathion is in the United States by prescription only, but the lotion's high alcohol content makes it extremely flammable, and its strong fumes can cause severe headaches.

Second, says Taplin, "there is no way, in a 'civilized society', that an effective treatment can be forced on a population so that everyone is treated at the same time."

And finally, says Mumcuoglu, "nature is more complex and clever than we think. Lice, like any insect, have lots of mechanisms to survive old and new pediculicides. They have adapted very well to their host, and therefore it is very difficult to eliminate them. In the best case, we can control them and diminish their number to somehow acceptable levels."

Indeed, statistics show that, except for the common cold, head lice infestation is more common than all the other childhood communicable conditions combined. In a review of the prevalence of head lice throughout the world from 1985-1997, The World Health Organization (WHO) reported that infestation rates are "high almost everywhere, both in developed and developing countries and in tropical and temperate countries. In many of the studies...infestations were found among 90 percent or more of the children."

Given this, controlling the problem is essential. Both Mumcuoglu and Maunder agree that repellents designed to prevent head lice are a good control mechanism.

"Effective repellents used daily, before a child is sent to school or kindergarten, could be a good way to protect them from infestation," said Mumcuoglu. Maunder agrees these repellents can be an effective deterrent. However, Taplin warns against daily or routine use of general insect repellents containing DEET, a very common ingredient in these products, to treat head lice. None are approved for this purpose, and can be irritating to the eyes and skin.

Regular combing can also detect and stop the establishment of a louse infestation, adds Mumcuoglu. The small number on a newly infested head could easily be eliminated.

A bit of history: head lice have been man's constant companion for many, many millennia. Evidence of lice has been found on Egyptian mummies and in the New World long before Columbus. Pliny, a Greek naturalist, suggested bathing in viper broth to rid oneself of them. Montezuma paid people to pick nits off his subjects, dried them, and saved them in his treasury. In 1657, the book Adam in Eden, or Nature's Paradise by W. Coles noted that the oil from hyssop "killeth lice."

In 1681, the book The English Physician Enlarged recommended tobacco juice to kill lice on children's heads, a very early reference to the use of tobacco as an insecticide. Over time, desperate physicians, parents and teachers have tried everything, including horse sweat and head shaving (now obsolete, notes Taplin) to end or prevent infestation. Finally, medical historians trace head lice infestations back 9,000 years.