Kosta Y. Mumcuoglu

Destruction of Bacteria in the Digestive Tract of the Maggot of Lucilia sericata (Diptera: Calliphoridae)

Abstract Green fluorescent protein-producing Escherichia coli were used to investigate the fate of bacteria in the alimentary tract of sterile grown maggots, Lucilia sericata (Meigen), using a laser scanning confocal microscope. A computer program was used to analyze the intensity of the fluorescence and to quantify the number of bacteria. The crop and the anterior midgut were the most heavily infected areas of the intestine. A significant decrease in the amount of bacteria was observed in the posterior midgut. The number of bacteria decreased even more significantly in the anterior hindgut and practically no bacteria were seen in the posterior end, near the anus. The viability of bacteria in the different gut sections was examined. It was shown that 66.7% of the crops, 52.8% of the midguts, 55.6% of the anterior hindguts, and 17.8% of posterior hindguts harbored living bacteria. In conclusion, during their passage through the digestive tract the majority of E. coli was destroyed in the midgut. Most of the remaining bacteria were killed in the hindgut, indicating that the feces were either sterile or contained only small numbers of bacteria.

Maggot therapy for the treatment of intractable wounds

Background Fly maggots have been known for centuries to help debride and heal wounds. Maggot therapy was first introduced in the USA in 1931 and was routinely used there until the mid‐1940s in over 300 hospitals. With the advent of antimicrobiols, maggot therapy became rare until the early 1990s, when it was re‐introduced in the USA, UK, and Israel. The objective of this study was to assess the efficacy of maggot therapy for the treatment of intractable, chronic wounds and ulcers in long‐term hospitalized patients in Israel.

Permethrin resistance in the head louse Pediculus capitis from Israel

Head lice, Pediculus capitis, were collected from children aged 3–12 years in Maale Adumin, a town near Jerusalem, after reports of control failure with the pyrethroid insecticide permethrin. A total of 1516 children were examined: living lice and eggs were found on 12.1% of the children; or another 22.8% of the children only nits were found. Twice as many girls as boys (8.1% v 4%) were infested with lice and or nits. Head lice collected from infested children were exposed to permethrin impregnated filter‐papers. Log time probit mortality (ltp) regression lines were calculated for mortality data and compared to ltp lines for a similar collection of head lice made in 1989. The regression lines for the two years were significantly different, with a 4‐fold decrease in susceptibility at the LT50 level between 1989 and 1994. The slopes of the lines also suggested that the 1994 population was more heterogenous in its response to permethrin than the 1989 population. In contrast, a laboratory population of body lice (Pediculus humanus) tested with the same batch of permethrin‐impregnated papers showed a slight but non‐significant increase in susceptibility between 1989 and 1994. The results suggest that resistance to pyrethroids has developed rapidly among head lice since permethrin was introduced in 1991 as a pediculicide in Israel.

Clinical Applications for Maggots in Wound Care

Maggot debridement therapy (MDT) was first introduced in the US in 1931 and was routinely used here until mid-1940s in over 300 hospitals. With the advent of antibacterials, maggot therapy became rare until the early 1990s, when it was re-introduced first in the US, and later in Israel, the UK, Germany, Sweden, Switzerland, Ukraine and Thailand.Sterile maggots of the green bottle fly, Lucilia (Phaenicia) sericata, are used for MDT. Up to 1000 maggots are introduced in the wound and left for 1 to 3 days. MDT could be used for any kind of purulent, sloughy wound on the skin, independent of the underlying diseases or the location on the body for ambulatory as well as for hospitalized patients. One of the major advantages of MDT is that the maggots separate the necrotic tissue from the living tissue, making a surgical debridement easier. In 80 to 95% of the cases, a complete or significant debridement of the wound is achieved. As therapy progresses, new layers of healthy tissue are formed over the wounds. The offensive odor emanating from the necrotic tissue and the intense pain accompanying the wound decrease significantly. In a significant number of patients, an immediate amputation can be prevented as a result of MDT. In other cases, a more proximal amputation could be avoided. It is also possible that in patients with deep wounds, where septicemia is a serious threat, this can be prevented as a result of MDT.The majority of patients do not complain of any major discomfort during the treatment. Psychological and esthetic considerations are obvious. Maggots can occasionally cause a tickling or itching sensation. Approximately 20 to 25% of the patients with superficial, painful wounds, complain of increased pain during treatment with maggots, and are treated with analgesics.MDT has been proven to be an effective method for cleaning chronic wounds and initiating granulation. It is a simple, efficient, well tolerated and cost-effective tool for the treatment of wounds and ulcers, which do not respond to conventional treatment and surgical intervention.

Antibacterial substances of low molecular weight isolated from the blowfly, Lucilia sericata.

Abstract Low molecular weight compounds were isolated by high‐performance liquid chromatography from the maggot or haemolymph extracts of Lucilia sericata (Meigen) (Diptera: Calliphoridae). Using gas chromatography‐mass spectrometry analysis, three compounds were obtained: p‐hydroxybenzoic acid (molecular weight 138 Da), p‐hydroxyphenylacetic acid (molecular weight 152 Da) and octahydro‐dipyrrolo[1,2‐a;1′,2′‐d] pyrazine‐5,10‐dione (molecular weight 194 Da), also known as the cyclic dimer of proline (or proline diketopiperazine or cyclo[Pro,Pro]). All three molecules revealed antibacterial activity when tested against Micrococcus luteus and/or Pseudomonas aeruginosa, and the effect was even more pronounced when these molecules were tested in combination and caused lysis of these bacteria.

Pyrethroid resistance mechanisms in the head louse Pediculus capitis from Israel: implications for control

In Israel, the head louse, Pediculus capitis, developed resistance to DDT through the extensive use of this insecticide until the 1980s. In 1991, permethrin was introduced for control of DDT resistant P. capitis in Israel, leading to control failure of this pyrethroid insecticide by 1994. Pyrethroid resistance of P. capitis in Israel extends to phenothrin, which has not been used for louse control. We identified a glutathione S‐transferase(GST)‐based mechanism of DDT resistance in the Israeli head lice. This GST mechanism occurred before 1989, while permethrin resistance in P. capitis developed after 1994, suggesting that the main GST resistance mechanism selected by DDT use does not confer any pyrethroid cross‐resistance. Esterase activity levels were equivalent in pyrethroid resistant and susceptible P. capitis field‐collected in Israel, and in a susceptible strain of P.humanus, the body louse, indicating no involvement of any esterase‐based mechanism in resistance. A weak monooxygenase‐based permethrin metabolism resistance mechanism was the only factor identified which could account for any of the observed pyrethroid resistance in P. capitis. However, the lack of synergism of phenothrin resistance by piperonyl butoxide suggests that a non‐oxidative mechanism is also present in the resistant lice. Therefore it seems probable that pyrethroid resistance in Israeli P. capitis is due to a combination of nerve insensitivity (knockdown resistance or ‘kdr’) and monooxygenase resistance mechanisms.

In vitro Antibacterial Activity of Lucilia sericata Maggot Secretions

Maggots of the green blowfly, Lucilia sericata, are used as an alternative to surgical intervention and long-term antiseptic therapy for the treatment of chronic wounds. The secretions of maggots are known to have antibacterial properties. To quantify the bactericidal effect of secretions from larvae of L. sericata, an in vitro test model based on the modified European quantitative suspension test (EN 1040) was developed, in which a co-culture of maggots and bacteria (Micrococcus luteus,Escherichia coli, methicillin-sensitive Staphylo-coccus aureus) in tryptic soy broth was tested. The numbers of bacterial colonies with and without maggot exposure were compared after 24, 48 and 72 h of exposure. The mean log10 reduction factor (RF) for bacterial elimination per maggot was >4 at all examined times for all tested bacteria. Thus, maggot secretion fulfilled the required definitions of an antiseptic. In addition, the maggots’ ability to ingest bacteria was also evaluated. Maggots contained viable bacteria after 48 h of contact with the respective organisms. These maggots also continued excreting bacteria. Therefore, maggots should be disposed of after use as they must be regarded as medical waste.

Prevention and Treatment of Head Lice in Children

Head louse infestations (pediculosis) are prevalent worldwide. In developed countries, the infestation rate of 4- to 13-year-old children remains high despite preventive efforts. This is due to the existence of numerous ineffective pediculicides, the incorrect use of the effective agents, toxicological concerns and the development of louse strains resistant to insecticides.One of the most effective tools for the prevention and control of lice is the louse comb, which should be used regularly for the detection of living lice at an early stage of infestation, and as an accessory to any treatment method to remove living and dead lice. The louse comb can also be used systematically for the treatment of infestations, for confirmation that treatment with pediculicides has been successful, and for the removal of nits (dead eggs or egg shells).Most pediculicides are only partially ovicidal. Therefore, 10 days after beginning treatment with any antilouse product, the scalp of the child should be examined. If no living lice are found, the treatment should be discontinued. If living lice are still present, treatment should be continued with a product containing a different active ingredient.Suffocating agents such as olive, soya, sunflower and corn oils, hair gels and mayonnaise are able to kill a significant number of lice only if they are applied in liberal quantities for more than 12 hours. However, they lubricate the hair and therefore may facilitate combing and removing lice and eggs from the scalp.Nits may remain glued on the hair for at least 6 months, even after a successful treatment, and lead to a false positive diagnosis of louse infestation. If nits are seen on the hair, the child should be examined, but treatment should be initiated only if living lice are found. Formulations containing 5% acetic acid or 8% formic acid, as well as acid shampoos (pH 4.5 to 5.5) and conditioners, in combination with a louse comb, can be helpful for removing nits.There is no conclusive evidence that using essential oils to repel lice is effective. Regular examination of the child’s head using a louse comb is the best measure to detect re-infestation at an early stage. Educating caregivers, nurses and teachers about louse biology, epidemiology, prevention and control is of paramount importance. The psychological effect of an infestation with lice is significant and often associated with anxiety and fear. The child should not be made to feel responsible for having lice, or be punished or reprimanded.

Molecular Detection and Characterization of Tick-borne Pathogens in Dogs and Ticks from Nigeria

Background Only limited information is currently available on the prevalence of vector borne and zoonotic pathogens in dogs and ticks in Nigeria. The aim of this study was to use molecular techniques to detect and characterize vector borne pathogens in dogs and ticks from Nigeria. Methodology/Principal Findings Blood samples and ticks (Rhipicephalus sanguineus, Rhipicephalus turanicus and Heamaphysalis leachi) collected from 181 dogs from Nigeria were molecularly screened for human and animal vector-borne pathogens by PCR and sequencing. DNA of Hepatozoon canis (41.4%), Ehrlichia canis (12.7%), Rickettsia spp. (8.8%), Babesia rossi (6.6%), Anaplasma platys (6.6%), Babesia vogeli (0.6%) and Theileria sp. (0.6%) was detected in the blood samples. DNA of E. canis (23.7%), H. canis (21.1%), Rickettsia spp. (10.5%), Candidatus Neoehrlichia mikurensis (5.3%) and A. platys (1.9%) was detected in 258 ticks collected from 42 of the 181 dogs. Co- infections with two pathogens were present in 37% of the dogs examined and one dog was co-infected with 3 pathogens. DNA of Rickettsia conorii israelensis was detected in one dog and Rhipicephalus sanguineus tick. DNA of another human pathogen, Candidatus N. mikurensis was detected in Rhipicephalus sanguineus and Heamaphysalis leachi ticks, and is the first description of Candidatus N. mikurensis in Africa. The Theileria sp. DNA detected in a local dog in this study had 98% sequence identity to Theileria ovis from sheep. Conclusions/Significance The results of this study indicate that human and animal pathogens are abundant in dogs and their ticks in Nigeria and portray the potential high risk of human exposure to infection with these agents.

Evidence from mitochondrial DNA that head lice and body lice of humans (Phthiraptera: Pediculidae) are conspecific

Abstract The specific status of the head and body lice of humans has been debated for more than 200 yr. To clarify the specific status of head and body lice, we sequenced 524 base pairs (bp) of the cytochrome oxidase I (COI) gene of 28 head and 28 body lice from nine countries. Ten haplotypes that differed by 1–5 bp at 11 nucleotide positions were identified. A phylogeny of these sequences indicates that these head and body lice are not from reciprocally monophyletic lineages. Indeed, head and body lice share three of the 10 haplotypes we found. FST values and exact tests of haplotype frequencies showed significant differences between head and body lice. However, the same tests also showed significant differences among lice from different countries. Indeed, more of the variation in haplotype frequencies was explained by differences among lice from different countries than by differences between head and body lice. Our results indicate the following: (1) head and body lice do not represent reciprocally monophyletic lineages and are conspecific; (2) gene flow among populations of lice from different countries is limited; and (3) frequencies of COI haplotypes can be used to study maternal gene flow among populations of head and body lice and thus transmission of lice among their human hosts.