The origin and distribution of human lice in the world

Pediculosis capitis is a growing neglected infestation due to migration in southeast Turkey

Demographic, socio-economical, and environmental changes affecting prevalence of Pediculosis capitis. The aim of this study was to investigate the prevalence of P. capitis and external factors affecting the distribution of P. capitis. A total of 6004 primary-school students between 5 and 11 years were screened for P. capitis at 28 different primary-schools in Gaziantep, located in southeastern of Turkey, during different two education terms (First education term is in September 2013 to May 2014, second education term is in September 2014 and May 2015). The prevalence of P. capitis was found to be positive 1.5 % (90/6004) and 6.9 % (415/6004) in first education term and in second education term, respectively. In this study shown that the rate of P. capitis's prevalence was increased 5.4 % in Gaziantep. P. capitis is a neglected infestation and it has re-emerged in Gaziantep, located in the southeastern of Turkey. Health staff member must improve health education programs in primary-school students especially girl students.

Studies of Ancient Lice Reveal Unsuspected Past Migrations of Vectors

Lice are among the oldest parasites of humans representing an excellent marker of the evolution and migration of our species over time. Here, we analyzed by real-time polymerase chain reaction (RT-PCR) developed in this study the mitochondrial DNA of seven ancient head louse eggs found on hair remains recovered from two sites in Israel: 1) five nits dating from Chalcolithic period (4,000 bc) were found in the Cave of the Treasure located at Nahal Mishmar, in the Judean Desert and 2) two nits dating from Early Islamic Period (ad 650-810) were found in Nahal Omer in the Arava Valley (between Dead Sea and Red Sea). Our results suggest that these eggs belonged to people originating from west Africa based on identification of the louse mitochondrial sub-clade specific to that region.

Molecular survey of the head louse Pediculus humanus capitis in Thailand and its potential role for transmitting Acinetobacter spp

BACKGROUND

Head louse infestation, which is caused by Pediculus humanus capitis, occurs throughout the world. With the advent of molecular techniques, head lice have been classified into three clades. Recent reports have demonstrated that pathogenic organisms could be found in head lice. Head lice and their pathogenic bacteria in Thailand have never been investigated. In this study, we determined the genetic diversity of head lice collected from various areas of Thailand and demonstrated the presence of Acinetobacter spp. in head lice.

METHODS

Total DNA was extracted from 275 head louse samples that were collected from several geographic regions of Thailand. PCR was used to amplify the head louse COI gene and for detection of Bartonella spp. and Acinetobacter spp. The amplified PCR amplicons were cloned and sequenced. The DNA sequences were analyzed via the neighbor-joining method using Kimura's 2-parameter model.

RESULTS

The phylogenetic tree based on the COI gene revealed that head lice in Thailand are clearly classified into two clades (A and C). Bartonella spp. was not detected in all the samples, whereas Acinetobacter spp. was detected in 10 samples (3.62%), which consisted of A. baumannii (1.45%), A. radioresistens (1.45%), and A. schindleri (0.72%). The relationship of Acinetobacter spp. and the head lice clades showed that Acinetobacter spp. was found in clade A and C.

CONCLUSIONS

Head lice in Thailand are classified into clade A and B based on the COI gene sequences. Pathogenic Acinetobacter spp. was detected in both clades. The data obtained from the study might assist in the development of effective strategies for head lice control in the future. Detection of pathogenic bacteria in head lice could raise awareness of head lice as a source of nosocomial bacterial infections.