Former director of National institute of communicable diseases (NICD) Dr P N Seghal on Friday said that the incidence of P. falciparum malaria, causing cerebral morbidity, had shown a marginal increase in Hyderabad state in the recent past.Dr Seghal, who was here to take part in the three-day training programmes on malaria control held from June 1 in his capacity as the consultant of Voluntary health association of India (VHAI), told reporters that Hyderabad, Visakhapatnam and Vijayawada were among the 15 cities identified in the country as high risk areas.