(Reuters) - The
number of people living with multiple sclerosis around the world has increased
by 10 percent in the past five years to 2.3 million, according to the most
extensive survey of the disease to date.
The debilitating
neurological condition, which affects twice as many women as men, is found in
every region of the world, although prevalence rates vary widely.
Multiple sclerosis
(MS) is most common in North America and Europe, at 140 and 108 cases per
100,000 respectively, while in sub-Saharan Africa the rate is just 2.1 per
100,000, the Multiple Sclerosis International Federation's Atlas of MS 2013
showed on Wednesday.
The atlas also confirmed
that MS occurs significantly more in countries at high latitude, with Sweden
having the highest rate in Europe and Argentina having more cases than countries further north in Latin
America.
The reason for the
link to high latitudes is unclear but some scientists have suggested that
exposure to sunlight may reduce the incidence of the disease.
The survey found a
big increases in the number of medical experts trained to diagnose MS and help
patients with treatment, while the number of magnetic resonance imaging (MRI)
machines available to carry out scans has doubled in emerging countries.
But huge disparities
remain when it comes to access to modern disease-modifying drugs.
MS medicine has seen
a number of advances in recent years, particularly with the introduction of a
new generation of oral therapies such as Novartis' Gilenya, Biogen Idec's
Tecfidera and Sanofi's Aubagio.
These medicines offer
an effective alternative to older disease-modifying treatments that are given
by injection.
The survey found that
injectable drugs like Biogen's Avonex and Teva's Copaxone were partly or fully
funded in 96 percent of high-income countries, while Gilenya was available in
76 percent.
However, none of
these drugs was available under government programmes in low-income countries.
(Reporting by Ben Hirschler; Editing by Alistair Lyon)
