Larvicidal and ovicidal activities of phenyl acetic acid isolated from Streptomyces collinus against Culex quinquefasciatus Say and Aedes aegypti L. (Diptera: Culicidae).

The bio-efficacy of crude ethyl acetate extract, fractions and a compound phenyl acetic acid from the ethyl acetate extract of Streptomyces collinus was evaluated on Culex quinquefasciatus Say and Aedes aegypti L. mosquitoes (Diptera: Culicidae). The larvae were exposed to concentrations of 2.5, 5.0, 7.5 and 10.0 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the larval mortality was assessed and the LC50 and LC90 values were calculated. Similarly, per cent ovicidal activity was calculated for eggs after 120 h post treatment for phenyl acetic acid. Among the eleven fractions screened, fraction 7 from the ethyl acetate extract of Streptomyces collinus exhibited good larvicidal activity against both mosquito species. The LC50 and LC90 values of fraction 7 were 4.42, 6.23 ppm against Cx. quinquefasciatus larvae and 5.13, 14.51 ppm against Ae. aegypti larvae, respectively. Further, the isolated compound, phenyl acetic acid from fraction 7 recorded 100% larvicidal activity at 2 ppm concentration with LC50 and LC90 values of 2.07, 4.87 ppm on Cx. quinquefasciatus larvae and 3.81, 9.87 ppm on Ae. aegypti larvae, respectively. Phenyl acetic acid presented 50.3% and 42.0% ovicidal activity against Cx. quinquefasciatus and Ae. aegypti eggs at 2 ppm concentration after 120 h post treatment. The compound, phenyl acetic acid could be used in mosquito control programme.

COVID-19 lockdown: impact assessment on Aedes larval indices, breeding habitats, effects on vector control programme and prevention of dengue outbreaks.

Aedes aegypti (Linn.) and Aedes albopictus (Skuse) are widespread vector mosquitoes responsible for the transmission of various disease-causing viruses to human including dengue virus (DENV). India is endemic for dengue disease and both of these vector mosquitoes are well established throughout India. Since, Aedes mosquitoes breeds in containers, WHO recommends to do a regular immature surveillance and implement appropriate control measures. Owing to the current COVID-19 pandemic, most of the countries have implemented continuous shutdown/lockdown, which affected the routine Aedes surveillance and vector control measures. In India, the first nation-wide lockdown was implemented on 24th, March 2020. As of now, Government of India has extended the lockdown till 30th, June 2020. In the present study, two rounds of Aedes surveillance was carried out in two localities of Bengaluru City (urban) of Karnataka State, India during the COVID-19 lockdown days and results were compared with pre-lockdown surveillance data to assess the impact of lockdown on Aedes larval indices, breeding habitats and dengue vector control programme. The recorded house index (HI) and Breteau index (BI) were 6.6 and 9.3 in K.P. Agrahara and 4.0 and 5.3 in Palace Guttahalli during pre-lockdown survey. The house index (HI) and Breteau index (BI) were found to be increased to 26.6 and 34.6 in K.P. Agrahara and 21.3 and 28.0 in Palace Guttahalli during the COVID-19 lockdown second survey. Aedes immature density has drastically increased in both the localities due to temporarily discontinued Aedes surveillance, larval control activities like source reduction and anti-larval measures during COVID-19 lockdown. The high indices show that the vector is increasing and this may result in higher dengue virus transmission. The results highly recommend to implement the Aedes vector control programme with limited health staffs following the physical distance and other protectives measures to prevent dengue outbreaks.

Mucormycosis of the middle ear: a case report with review of literature.

Mucor is a saprophytic organism and commonly invades the nose and paranasal sinuses of immunocompromised and diabetic patients involvement of the middle ear and mastoid in a nondiabetic patients is very rare and this may be the first case report clinical presentation of ear pain with reference to the mastoid and upper neck may be the early symptoms unlike the foul smelling ear discharge as seen in atticoantral disease. Radical debridement in the form of M.R.M with or without the use of amphotericin B may suffice in non-diabetic patients this case is reported to highlight the point that mucormycosis can also involve middle ear and mastoid in nondiabetic patients.

Frontal sinus osteoma: a difficult surgical decision in the era of endoscopic sinus surgery.

A slow-growing frontal sinus osteoma has been followed up since the year 2001 by clinical, endoscopic, and radiological examination in the Department of Otolaryngology, New Medical Centre Specialty Hospital, Abu Dhabi, for 10 years until the year 2010. The last computed tomography scan of paranasal sinuses was done on April 5, 2010, which revealed increasing size of the osteoma by 38.1 mm; and it has become symptomatic. No specific cause of the sudden change of growth of the osteoma could be evaluated from the history and clinical examination. There was an increase in the frequency of headache and feeling of pressure in the forehead. Choice of surgical approach was difficult in this popular era of endonasal endoscopic sinus approach. A great deal of effort was made after reviewing the literature and consultation with the radiologist and neurosurgeon to accept the bicoronal osteoplastic flap approach. A broad-based posterior frontal sinus is found to be ideal for external approach.