This photo of a baby on an IV drip is going viral for an upsetting reason

One of the greatest advances humans have ever made has been using vaccines to eradicate diseases.

Now we're being reminded of just how important they are after a baby caught a rare illness usually combatted with vaccination. Alecia Rankin, a woman from Tennessee in the US, shared an image of her seven-week-old niece in hospital this week. In the photo, baby Aryn can be seen with an IV drip in her head. Alecia explained in a Facebook post that the baby was hospitalised with Hib flu, a bacteria that can in some cases spread to the blood stream or nervous system and become fatal. "Reason #1736493983283763 to vaccinate your kids," she captioned the image. Hib flu had almost been wiped out in first-world countries where vaccines are available and is still "so rare that [Aryn's] doctor hasn’t seen it in her career." Babies usually get the vaccine at two months, which is why Aryn hadn't had hers, but Alecia wants everyone to know how severe the illness can be. "Before you decide not to vaccinate your children because 'it’s your choice' and 'those who are vaccinated won’t be affected' remember that babies can get sick before they have the chance to get their vaccine," she wrote. Aryn had a spinal tap to test for meningitis and thankfully was OK and was able to go home, but the image of her tiny head with an IV drip in it is a worthy reminder of how vital it is to vaccinate kids.