While we are closer than ever to achieving EMTCT of HIV, gaps continue to exist. The majority of new HIV infections among children occur during the breastfeeding period. This requires greater focus on adherence to medicines and retaining mothers and infants in care to the end of the breastfeeding period and beyond. At the same time, treatment gains for children have not kept up with prevention. Less than half of the million children (aged 0–14) living with HIV around the world in 2016 did not receive ART, and when they did receive it, often it came too late. Without timely treatment, one third of children with HIV die before their second birthday. On average children living with HIV started treatment at the age of in sub-Saharan Africa.
For a sample from a continuous distribution, such as [..., ..., ..., ..., ...], the concept is unusable in its raw form, since each value will occur precisely once. The usual practice is to discretize the data by assigning frequency values to interval s of equal distance, as for making a histogram , effectively replacing the values by the midpoints of the intervals they are assigned to. The mode is then the value where the histogram reaches its peak. For small or middle-sized samples the outcome of this procedure is sensitive to the choice of interval width if chosen too narrow or too wide; typically one should have a sizable fraction of the data concentrated in a relatively small number of intervals (5 to 10), while the fraction of the data falling outside these intervals is also sizable. An alternate approach is kernel density estimation , which essentially blurs point samples to produce a continuous estimate of the probability density function which can provide an estimate of the mode.