With Guinea facing its gravest cholera outbreak since 2007, some residents of the capital Conakry are clamouring to be vaccinated.
Conakry - where rubbish is piled high at every turn, many neighbourhoods flood regularly and just 2.2 percent of households are linked to a sewage system - has seen at least 3,630 cases of cholera this year, according to the World Health Organization (WHO), making it by far the hardest-hit area.
"We're facing that pressure," said Sakoba Keïta, head of disease prevention in the Guinean Health Ministry. "Some Conakry residents hear that their home communities have been spared thanks to the vaccine and they want protection too."
The cholera vaccine has shown promising results in the handful of communities where it has been used: none of those vaccinated have been infected.
Protection from cholera is generally assured with proper hygiene, good sanitation and access to safe water; it is precisely because of Guinea's lack of water and sanitation systems that the vaccine has an important role, health experts say.
As of 4 September 5,938 people across Guinea were reported infected with cholera - a bacterial illness that can kill within hours if untreated - with 111 deaths, according to the UN Office for the Coordination of Humanitarian Affairs (OCHA).
Why not Sierra Leone?
There is no plan to use the cholera vaccine in Sierra Leone at this point, according to MSF communications officer Niklas Bergstrand. "Freetown [the capital] is such a big area - we'd have to vaccinate at least one million people which would be logistically very difficult," he told IRIN.
"Generally if we do cholera vaccination it's in a more limited area such as a refugee camp, or in targeted zones as in the Guinea case. Vaccination in Sierra Leone would cost about 3.5 euros per person and we'd rather put our resources into treatment and other response efforts."
Neighbouring Sierra Leone is facing its worst cholera epidemic since 1995, with 15,834 cases, including 251 deaths as of 3 September, according to OCHA.
For now cholera vaccination is not generally done on a large scale. WHO and partner agencies are planning a cholera vaccine stockpile for epidemic control and looking at the possibility of introducing the two-dose oral vaccine into national immunization programmes in endemic areas.